diff --git a/.github/workflows/dev-pr-test.yml b/.github/workflows/dev-pr-test.yml
index ebc16054..3f555e84 100644
--- a/.github/workflows/dev-pr-test.yml
+++ b/.github/workflows/dev-pr-test.yml
@@ -17,11 +17,11 @@ jobs:
       - name: checkout
         uses: actions/checkout@v3
 
-      - name: Set up JDK 11
+      - name: Set up JDK 17
         uses: actions/setup-java@v3
         with:
-          java-version: '11'
-          distribution: 'adopt'
+          distribution: 'temurin'
+          java-version: '17'
 
       - name: Set application properties
         run: |
diff --git a/src/main/kotlin/upbrella/be/config/DevCorsConfig.kt b/src/main/kotlin/upbrella/be/config/DevCorsConfig.kt
index c62d2819..4ef35aab 100644
--- a/src/main/kotlin/upbrella/be/config/DevCorsConfig.kt
+++ b/src/main/kotlin/upbrella/be/config/DevCorsConfig.kt
@@ -2,11 +2,9 @@ package upbrella.be.config
 
 import org.springframework.context.annotation.Profile
 import org.springframework.stereotype.Component
-
 import javax.servlet.*
 import javax.servlet.http.HttpServletRequest
 import javax.servlet.http.HttpServletResponse
-import java.io.IOException
 
 @Profile("dev")
 @Component
diff --git a/src/main/kotlin/upbrella/be/rent/controller/RentController.kt b/src/main/kotlin/upbrella/be/rent/controller/RentController.kt
index f9cd1f6c..303fb393 100644
--- a/src/main/kotlin/upbrella/be/rent/controller/RentController.kt
+++ b/src/main/kotlin/upbrella/be/rent/controller/RentController.kt
@@ -12,7 +12,7 @@ import upbrella.be.rent.service.ConditionReportService
 import upbrella.be.rent.service.ImprovementReportService
 import upbrella.be.rent.service.LockerService
 import upbrella.be.rent.service.RentService
-import upbrella.be.slack.service.SlackAlarmService
+import upbrella.be.slack.SlackAlarmService
 import upbrella.be.user.dto.response.SessionUser
 import upbrella.be.user.repository.UserReader
 import upbrella.be.util.CustomResponse
@@ -97,9 +97,7 @@ class RentController(
         val userToReturn = userReader.findUserById(user.id)
 
         rentService.returnUmbrellaByUser(userToReturn, returnUmbrellaByUserRequest)
-        val unrefundedRentCount = rentService.countUnrefundedRent()
 
-        slackAlarmService.notifyReturn(unrefundedRentCount)
         return ResponseEntity
             .ok()
             .body(CustomResponse(
diff --git a/src/main/kotlin/upbrella/be/rent/dto/response/ConditionReportResponse.kt b/src/main/kotlin/upbrella/be/rent/dto/response/ConditionReportResponse.kt
index 443e0719..c67a0bbb 100644
--- a/src/main/kotlin/upbrella/be/rent/dto/response/ConditionReportResponse.kt
+++ b/src/main/kotlin/upbrella/be/rent/dto/response/ConditionReportResponse.kt
@@ -11,7 +11,7 @@ data class ConditionReportResponse(
     companion object {
         fun fromConditionReport(conditionReport: ConditionReport): ConditionReportResponse {
             return ConditionReportResponse(
-                id = conditionReport.history!!.id!!,
+                id = conditionReport.history.id!!,
                 umbrellaUuid = conditionReport.history.umbrella.uuid,
                 content = conditionReport.content,
                 etc = conditionReport.etc
diff --git a/src/main/kotlin/upbrella/be/rent/dto/response/ImprovementReportResponse.kt b/src/main/kotlin/upbrella/be/rent/dto/response/ImprovementReportResponse.kt
index 819dfcd8..d77258b9 100644
--- a/src/main/kotlin/upbrella/be/rent/dto/response/ImprovementReportResponse.kt
+++ b/src/main/kotlin/upbrella/be/rent/dto/response/ImprovementReportResponse.kt
@@ -11,8 +11,8 @@ data class ImprovementReportResponse(
     companion object {
         fun fromImprovementReport(improvementReport: ImprovementReport): ImprovementReportResponse {
             return ImprovementReportResponse(
-                id = improvementReport.history?.id ?: 0,
-                umbrellaUuid = improvementReport.history?.umbrella?.uuid ?: 0,
+                id = improvementReport.history.id ?: 0,
+                umbrellaUuid = improvementReport.history.umbrella.uuid,
                 content = improvementReport.content,
                 etc = improvementReport.etc
             )
diff --git a/src/main/kotlin/upbrella/be/rent/dto/response/RentalHistoryResponse.kt b/src/main/kotlin/upbrella/be/rent/dto/response/RentalHistoryResponse.kt
index 089ed35b..0dffe915 100644
--- a/src/main/kotlin/upbrella/be/rent/dto/response/RentalHistoryResponse.kt
+++ b/src/main/kotlin/upbrella/be/rent/dto/response/RentalHistoryResponse.kt
@@ -2,7 +2,6 @@ package upbrella.be.rent.dto.response
 
 import com.fasterxml.jackson.annotation.JsonFormat
 import java.time.LocalDateTime
-import upbrella.be.rent.entity.History
 
 data class RentalHistoryResponse(
     val id: Long,
@@ -24,9 +23,6 @@ data class RentalHistoryResponse(
     val etc: String? = null
 ) {
     companion object {
-        private fun isRefunded(history: History): Boolean {
-            return history.refundedAt != null
-        }
 
         fun createReturnedHistory(history: HistoryInfoDto, elapsedDay: Int, totalRentalDay: Int): RentalHistoryResponse {
             return RentalHistoryResponse(
diff --git a/src/main/kotlin/upbrella/be/rent/entity/ConditionReport.kt b/src/main/kotlin/upbrella/be/rent/entity/ConditionReport.kt
index 45b35c16..aa8dba1b 100644
--- a/src/main/kotlin/upbrella/be/rent/entity/ConditionReport.kt
+++ b/src/main/kotlin/upbrella/be/rent/entity/ConditionReport.kt
@@ -6,7 +6,7 @@ import javax.persistence.*
 class ConditionReport(
     @OneToOne
     @JoinColumn(name = "history_id")
-    val history: History? = null,
+    val history: History,
     val content: String? = null,
     val etc: String? = null,
     @Id
diff --git a/src/main/kotlin/upbrella/be/rent/entity/History.kt b/src/main/kotlin/upbrella/be/rent/entity/History.kt
index 0d92214b..ad92e04b 100644
--- a/src/main/kotlin/upbrella/be/rent/entity/History.kt
+++ b/src/main/kotlin/upbrella/be/rent/entity/History.kt
@@ -1,6 +1,5 @@
 package upbrella.be.rent.entity
 
-import upbrella.be.rent.dto.request.ReturnUmbrellaByUserRequest
 import upbrella.be.rent.exception.NotRefundedException
 import upbrella.be.store.entity.StoreMeta
 import upbrella.be.umbrella.entity.Umbrella
@@ -25,11 +24,11 @@ class History(
 
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "rent_store_meta_id")
-    val rentStoreMeta: StoreMeta,
+    var rentStoreMeta: StoreMeta,
 
     @ManyToOne(fetch = FetchType.LAZY)
     @JoinColumn(name = "return_store_meta_id")
-    val returnStoreMeta: StoreMeta? = null,
+    var returnStoreMeta: StoreMeta? = null,
 
     val rentedAt: LocalDateTime = LocalDateTime.now(),
     var returnedAt: LocalDateTime? = null,
@@ -60,26 +59,6 @@ class History(
             )
         }
 
-        @JvmStatic
-        fun updateHistoryForReturn(
-            rentedHistory: History,
-            returnStoreMeta: StoreMeta,
-            request: ReturnUmbrellaByUserRequest
-        ): History {
-            return History(
-                id = rentedHistory.id,
-                umbrella =  rentedHistory.umbrella,
-                user = rentedHistory.user,
-                paidAt =  rentedHistory.paidAt,
-                bank = request.bank,
-                accountNumber = request.accountNumber,
-                rentStoreMeta = rentedHistory.rentStoreMeta,
-                returnStoreMeta = returnStoreMeta,
-                rentedAt = rentedHistory.rentedAt,
-                returnedAt = LocalDateTime.now(),
-            )
-        }
-
         fun ofUserHistory(history: History): SingleHistoryResponse {
             var isReturned = true
             var isRefunded = false
@@ -139,4 +118,4 @@ class History(
         this.bank = null
         this.accountNumber = null
     }
-}
\ No newline at end of file
+}
diff --git a/src/main/kotlin/upbrella/be/rent/entity/ImprovementReport.kt b/src/main/kotlin/upbrella/be/rent/entity/ImprovementReport.kt
index 5138284e..cd6ca6f1 100644
--- a/src/main/kotlin/upbrella/be/rent/entity/ImprovementReport.kt
+++ b/src/main/kotlin/upbrella/be/rent/entity/ImprovementReport.kt
@@ -6,20 +6,10 @@ import javax.persistence.*
 class ImprovementReport(
     @OneToOne
     @JoinColumn(name = "history_id")
-    val history: History? = null,
+    val history: History,
     val content: String? = null,
     val etc: String? = null,
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
-    val id: Long? =null
-) {
-    companion object {
-        @JvmStatic
-        fun createFromReturn(history: History, content: String): ImprovementReport {
-            return ImprovementReport(
-                history = history,
-                content = content,
-            )
-        }
-    }
-}
\ No newline at end of file
+    val id: Long? = null
+)
diff --git a/src/main/kotlin/upbrella/be/rent/repository/ConditionReportRepository.kt b/src/main/kotlin/upbrella/be/rent/repository/ConditionReportRepository.kt
index 82a044a1..47c3d6c8 100644
--- a/src/main/kotlin/upbrella/be/rent/repository/ConditionReportRepository.kt
+++ b/src/main/kotlin/upbrella/be/rent/repository/ConditionReportRepository.kt
@@ -3,5 +3,4 @@ package upbrella.be.rent.repository
 import org.springframework.data.jpa.repository.JpaRepository
 import upbrella.be.rent.entity.ConditionReport
 
-interface ConditionReportRepository : JpaRepository<ConditionReport, Long> {
-}
\ No newline at end of file
+interface ConditionReportRepository : JpaRepository<ConditionReport, Long>
diff --git a/src/main/kotlin/upbrella/be/rent/repository/ImprovementReportRepository.kt b/src/main/kotlin/upbrella/be/rent/repository/ImprovementReportRepository.kt
index c0819bfc..12dac08d 100644
--- a/src/main/kotlin/upbrella/be/rent/repository/ImprovementReportRepository.kt
+++ b/src/main/kotlin/upbrella/be/rent/repository/ImprovementReportRepository.kt
@@ -3,5 +3,4 @@ package upbrella.be.rent.repository
 import org.springframework.data.jpa.repository.JpaRepository
 import upbrella.be.rent.entity.ImprovementReport
 
-interface ImprovementReportRepository : JpaRepository<ImprovementReport, Long> {
-}
\ No newline at end of file
+interface ImprovementReportRepository : JpaRepository<ImprovementReport, Long>
diff --git a/src/main/kotlin/upbrella/be/rent/repository/RentRepositoryImpl.kt b/src/main/kotlin/upbrella/be/rent/repository/RentRepositoryImpl.kt
index c4704af8..fd2dabc3 100644
--- a/src/main/kotlin/upbrella/be/rent/repository/RentRepositoryImpl.kt
+++ b/src/main/kotlin/upbrella/be/rent/repository/RentRepositoryImpl.kt
@@ -27,7 +27,7 @@ class RentRepositoryImpl(
             .orderBy(history.id.desc())
             .offset(pageable.offset)
             .limit(pageable.pageSize.toLong())
-            .fetch();
+            .fetch()
     }
 
     override fun findHistoryInfos(
@@ -61,7 +61,7 @@ class RentRepositoryImpl(
             .orderBy(history.id.desc())
             .offset(pageable.offset)
             .limit(pageable.pageSize.toLong())
-            .fetch();
+            .fetch()
     }
 
     override fun countAll(filter: HistoryFilterRequest, pageable: Pageable): Long {
@@ -82,12 +82,12 @@ class RentRepositoryImpl(
             .leftJoin(history.returnStoreMeta, storeMeta).fetchJoin()
             .where(history.user.id.eq(userId))
             .orderBy(history.id.desc())
-            .fetch();
+            .fetch()
     }
 
     private fun filterRefunded(filter: HistoryFilterRequest): BooleanExpression? {
         if (filter.refunded == null) {
-            return null;
+            return null
         }
 
         if (filter.refunded == true) {
@@ -96,4 +96,4 @@ class RentRepositoryImpl(
 
         return history.refundedAt.isNull
     }
-}
\ No newline at end of file
+}
diff --git a/src/main/kotlin/upbrella/be/rent/service/ImprovementReportService.kt b/src/main/kotlin/upbrella/be/rent/service/ImprovementReportService.kt
index 7faea2ac..e991ec4d 100644
--- a/src/main/kotlin/upbrella/be/rent/service/ImprovementReportService.kt
+++ b/src/main/kotlin/upbrella/be/rent/service/ImprovementReportService.kt
@@ -3,7 +3,6 @@ package upbrella.be.rent.service
 import org.springframework.stereotype.Service
 import upbrella.be.rent.dto.response.ImprovementReportPageResponse
 import upbrella.be.rent.dto.response.ImprovementReportResponse
-import upbrella.be.rent.entity.History
 import upbrella.be.rent.entity.ImprovementReport
 import upbrella.be.rent.repository.ImprovementReportRepository
 
@@ -15,9 +14,9 @@ class ImprovementReportService(
     fun findAll(): ImprovementReportPageResponse =
         ImprovementReportPageResponse.of(findAllImprovementReport())
 
-    fun addImprovementReportFromReturn(history: History, content: String) {
-        val report = ImprovementReport.createFromReturn(history, content)
-        improvementReportRepository.save(report)
+    fun save(improvementReport: ImprovementReport) {
+
+        improvementReportRepository.save(improvementReport)
     }
 
     private fun findAllImprovementReport(): List<ImprovementReportResponse> =
diff --git a/src/main/kotlin/upbrella/be/rent/service/RentService.kt b/src/main/kotlin/upbrella/be/rent/service/RentService.kt
index 23f7b351..c3abc69a 100644
--- a/src/main/kotlin/upbrella/be/rent/service/RentService.kt
+++ b/src/main/kotlin/upbrella/be/rent/service/RentService.kt
@@ -9,8 +9,10 @@ import upbrella.be.rent.dto.request.ReturnUmbrellaByUserRequest
 import upbrella.be.rent.dto.response.*
 import upbrella.be.rent.entity.ConditionReport
 import upbrella.be.rent.entity.History
+import upbrella.be.rent.entity.ImprovementReport
 import upbrella.be.rent.exception.*
 import upbrella.be.rent.repository.RentRepository
+import upbrella.be.slack.SlackAlarmService
 import upbrella.be.store.entity.StoreMeta
 import upbrella.be.store.repository.StoreMetaReader
 import upbrella.be.umbrella.entity.Umbrella
@@ -30,6 +32,7 @@ import java.time.temporal.ChronoUnit
 class RentService(
     private val umbrellaService: UmbrellaService,
     private val storeMetaReader: StoreMetaReader,
+    private val slackAlarmService: SlackAlarmService,
     private val improvementReportService: ImprovementReportService,
     private val rentRepository: RentRepository,
     private val conditionReportService: ConditionReportService,
@@ -65,24 +68,31 @@ class RentService(
         rentRepository.findByUserIdAndReturnedAtIsNull(userToRent.id).ifPresent {
             throw ExistingUmbrellaForRentException("[ERROR] 해당 유저가 대여 중인 우산이 있습니다.")
         }
-        val willRentUmbrella = umbrellaService.findUmbrellaById(rentUmbrellaByUserRequest.umbrellaId)
-        if (willRentUmbrella.storeMeta.id != rentUmbrellaByUserRequest.storeId) {
+        val umbrella = umbrellaService.findUmbrellaById(rentUmbrellaByUserRequest.umbrellaId)
+        if (umbrella.storeMeta.id != rentUmbrellaByUserRequest.storeId) {
             throw UmbrellaStoreMissMatchException("[ERROR] 해당 우산은 해당 매장에 존재하지 않습니다.")
         }
-        if (willRentUmbrella.missed) {
+        if (umbrella.missed) {
             throw MissingUmbrellaException("[ERROR] 해당 우산은 분실되었습니다.")
         }
-        if (!willRentUmbrella.rentable) {
+        if (!umbrella.rentable) {
             throw NotAvailableUmbrellaException("[ERROR] 해당 우산은 대여중입니다.")
         }
-        willRentUmbrella.rentUmbrella()
+        umbrella.rentUmbrella()
         val rentalStore = storeMetaReader.findById(rentUmbrellaByUserRequest.storeId)
-        val conditionReport = rentUmbrellaByUserRequest.conditionReport
         val history = rentRepository.save(
-            History.ofCreatedByNewRent(willRentUmbrella, userToRent, rentalStore)
+            History.ofCreatedByNewRent(umbrella, userToRent, rentalStore)
         )
-        val conditionReportToSave = ConditionReport(history, conditionReport, null, null)
-        conditionReportService.saveConditionReport(conditionReportToSave)
+        slackAlarmService.notifyRent(userToRent, history)
+
+        rentUmbrellaByUserRequest.conditionReport
+            ?.takeIf { it.isNotBlank() }
+            ?.let { content ->
+                ConditionReport(history = history, content = content).also { conditionReport ->
+                    conditionReportService.saveConditionReport(conditionReport)
+                    slackAlarmService.notifyConditionReport(conditionReport)
+                }
+            }
     }
 
     @Transactional
@@ -91,15 +101,34 @@ class RentService(
         val history = rentRepository.findByUserIdAndReturnedAtIsNull(userToReturn.id)
             .orElseThrow { NonExistingUmbrellaForRentException("[ERROR] 해당 유저가 대여 중인 우산이 없습니다.") }
         val returnStore = storeMetaReader.findById(request.returnStoreId)
-        val updatedHistory = History.updateHistoryForReturn(history, returnStore, request)
+
+        history.bank = request.bank
+        history.accountNumber = request.accountNumber
+        history.returnStoreMeta = returnStore
+        history.returnedAt = LocalDateTime.now()
+
         val returnedUmbrella: Umbrella = history.umbrella
         returnedUmbrella.returnUmbrella(returnStore)
-        rentRepository.save(updatedHistory)
-        addImprovementReportFromReturnByUser(updatedHistory, request)
+
+        val unrefundedRentCount = countUnrefundedRent()
+
+        slackAlarmService.notifyReturn(userToReturn, history, unrefundedRentCount)
+        rentRepository.save(history)
+
+        request.improvementReportContent?.takeIf { it.isNotBlank() }
+            ?.let { content ->
+                ImprovementReport(history = history, content = content).also { improvementReport ->
+                    improvementReportService.save(improvementReport)
+                    slackAlarmService.notifyImprovementReport(improvementReport)
+                }
+            }
     }
 
     @Transactional
-    fun findAllHistories(filter: HistoryFilterRequest, pageable: Pageable): RentalHistoriesPageResponse {
+    fun findAllHistories(
+        filter: HistoryFilterRequest,
+        pageable: Pageable
+    ): RentalHistoriesPageResponse {
         val countOfAllHistories = rentRepository.countAll(filter, pageable)
         val countOfAllPages = countOfAllHistories / pageable.pageSize
         val rentalHistories = findAllRentalHistory(filter, pageable)
@@ -109,19 +138,16 @@ class RentService(
     fun findAllHistoriesByUser(userId: Long): AllHistoryResponse =
         AllHistoryResponse.of(findAllByUserId(userId))
 
-    private fun addImprovementReportFromReturnByUser(history: History, request: ReturnUmbrellaByUserRequest) {
-        request.improvementReportContent?.let { content ->
-            improvementReportService.addImprovementReportFromReturn(history, content)
-        }
-    }
-
     private fun findAllByUserId(userId: Long): List<SingleHistoryResponse> =
         findAllByUser(userId).map { toSingleHistoryResponse(it) }
 
     private fun findAllByUser(userId: Long): List<History> =
         rentRepository.findAllByUserId(userId)
 
-    private fun findAllRentalHistory(filter: HistoryFilterRequest, pageable: Pageable): List<RentalHistoryResponse> =
+    private fun findAllRentalHistory(
+        filter: HistoryFilterRequest,
+        pageable: Pageable
+    ): List<RentalHistoryResponse> =
         findHistoryInfos(filter, pageable).map { toRentalHistoryResponse(it) }
 
     private fun toSingleHistoryResponse(history: History): SingleHistoryResponse {
@@ -141,8 +167,14 @@ class RentService(
     private fun toRentalHistoryResponse(history: HistoryInfoDto): RentalHistoryResponse {
         var elapsedDay = ChronoUnit.DAYS.between(history.rentAt, LocalDateTime.now()).toInt()
         return if (history.returnAt != null) {
-            elapsedDay = ChronoUnit.DAYS.between(history.rentAt.toLocalDate(), history.returnAt.toLocalDate()).toInt()
-            val totalRentalDay = ChronoUnit.DAYS.between(history.rentAt.toLocalDate(), history.returnAt.toLocalDate()).toInt()
+            elapsedDay = ChronoUnit.DAYS.between(
+                history.rentAt.toLocalDate(),
+                history.returnAt.toLocalDate()
+            ).toInt()
+            val totalRentalDay = ChronoUnit.DAYS.between(
+                history.rentAt.toLocalDate(),
+                history.returnAt.toLocalDate()
+            ).toInt()
             RentalHistoryResponse.createReturnedHistory(history, elapsedDay, totalRentalDay)
         } else {
             RentalHistoryResponse.createNonReturnedHistory(history, elapsedDay)
@@ -187,6 +219,9 @@ class RentService(
         history.deleteBankAccount()
     }
 
-    private fun findHistoryInfos(filter: HistoryFilterRequest, pageable: Pageable): List<HistoryInfoDto> =
+    private fun findHistoryInfos(
+        filter: HistoryFilterRequest,
+        pageable: Pageable
+    ): List<HistoryInfoDto> =
         rentRepository.findHistoryInfos(filter, pageable)
 }
diff --git a/src/main/kotlin/upbrella/be/slack/SlackAlarmService.kt b/src/main/kotlin/upbrella/be/slack/SlackAlarmService.kt
new file mode 100644
index 00000000..b9466e8d
--- /dev/null
+++ b/src/main/kotlin/upbrella/be/slack/SlackAlarmService.kt
@@ -0,0 +1,72 @@
+package upbrella.be.slack
+
+import org.springframework.http.HttpEntity
+import org.springframework.http.HttpMethod.POST
+import org.springframework.stereotype.Service
+import org.springframework.web.client.RestTemplate
+import upbrella.be.config.SlackBotConfig
+import upbrella.be.rent.entity.ConditionReport
+import upbrella.be.rent.entity.History
+import upbrella.be.rent.entity.ImprovementReport
+import upbrella.be.user.entity.User
+
+@Service
+class SlackAlarmService(
+    private val slackBotConfig: SlackBotConfig,
+    private val restTemplate: RestTemplate
+) {
+
+    fun notifyRent(user: User, history: History) {
+        val message = buildString {
+            append("*우산 대여 알림: 입금을 확인해주세요.*\n\n")
+            append("사용자 ID : ${user.id}\n")
+            append("예금주 이름 : ${user.name}\n")
+            append("대여 지점 이름 : ${history.rentStoreMeta.name}\n")
+        }
+        send(message)
+    }
+
+    fun notifyReturn(user: User, history: History, unrefundedCount: Long) {
+        val message = buildString {
+            append("*우산 반납 알림: 보증금을 환급해주세요.*\n\n")
+            append("사용자 ID : ${user.id}\n")
+            append("대여 지점 이름 : ${history.rentStoreMeta.name}\n")
+            append("대여 시각: ${history.rentedAt}\n")
+            append("반납 지점 이름 : ${history.returnStoreMeta?.name}\n")
+            append("반납 시각: ${history.returnedAt}\n")
+            append("*잔여 환급 대기 건수* : $unrefundedCount")
+        }
+        send(message)
+    }
+
+    private fun send(message: String) {
+        val request = mutableMapOf<String, Any>(
+            "text" to message
+        )
+        val entity = HttpEntity(request)
+        restTemplate.exchange(slackBotConfig.webHookUrl, POST, entity, String::class.java)
+    }
+
+    fun notifyConditionReport(conditionReport: ConditionReport) {
+        val message = buildString {
+            append("*우산 상태 신고 접수*\n\n")
+            append("우산 ID : ${conditionReport.history.umbrella.id}\n")
+            append("대여 지점 이름 : ${conditionReport.history.rentStoreMeta.name}\n")
+            append("신고 내용 : ${conditionReport.content}\n")
+        }
+        send(message)
+    }
+
+    fun notifyImprovementReport(improvementReport: ImprovementReport) {
+        val message = buildString {
+            append("*우산 개선 사항 신고가 접수되었습니다.*\n\n")
+            append("우산 ID : ${improvementReport.history.umbrella.id}\n")
+            append("대여 지점 이름 : ${improvementReport.history.rentStoreMeta.name}\n")
+            append("대여 시각: ${improvementReport.history.rentedAt}\n")
+            append("반납 지점 이름 : ${improvementReport.history.returnStoreMeta?.name}\n")
+            append("반납 시각: ${improvementReport.history.returnedAt}\n")
+            append("신고 내용 : ${improvementReport.content}\n")
+        }
+        send(message)
+    }
+}
diff --git a/src/main/kotlin/upbrella/be/slack/slack/SlackAlarmService.kt b/src/main/kotlin/upbrella/be/slack/slack/SlackAlarmService.kt
deleted file mode 100644
index a893db43..00000000
--- a/src/main/kotlin/upbrella/be/slack/slack/SlackAlarmService.kt
+++ /dev/null
@@ -1,31 +0,0 @@
-package upbrella.be.slack.service
-
-import org.springframework.http.HttpEntity
-import org.springframework.http.HttpMethod.POST
-import org.springframework.stereotype.Service
-import org.springframework.web.client.RestTemplate
-import upbrella.be.config.SlackBotConfig
-
-@Service
-class SlackAlarmService(
-    private val slackBotConfig: SlackBotConfig,
-    private val restTemplate: RestTemplate
-) {
-
-    fun notifyReturn(unrefundedCount: Long) {
-        val message = buildString {
-            append("*우산이 반납되었습니다. 보증금을 환급해주세요.*\n\n")
-            append("*환급 대기 건수* : ")
-            append(unrefundedCount)
-        }
-        send(message)
-    }
-
-    private fun send(message: String) {
-        val request = mutableMapOf<String, Any>(
-            "text" to message
-        )
-        val entity = HttpEntity(request)
-        restTemplate.exchange(slackBotConfig.webHookUrl, POST, entity, String::class.java)
-    }
-}
diff --git a/src/main/kotlin/upbrella/be/store/dto/response/ImageUrlsResponse.kt b/src/main/kotlin/upbrella/be/store/dto/response/ImageUrlsResponse.kt
deleted file mode 100644
index 855ff454..00000000
--- a/src/main/kotlin/upbrella/be/store/dto/response/ImageUrlsResponse.kt
+++ /dev/null
@@ -1,5 +0,0 @@
-package upbrella.be.store.dto.response
-
-data class ImageUrlsResponse(
-    val imageUrls: List<String>
-)
diff --git a/src/main/kotlin/upbrella/be/store/entity/StoreDetail.kt b/src/main/kotlin/upbrella/be/store/entity/StoreDetail.kt
index 6a23d361..6651e317 100644
--- a/src/main/kotlin/upbrella/be/store/entity/StoreDetail.kt
+++ b/src/main/kotlin/upbrella/be/store/entity/StoreDetail.kt
@@ -3,7 +3,6 @@ package upbrella.be.store.entity
 import upbrella.be.store.dto.request.CreateStoreRequest
 import upbrella.be.store.dto.request.UpdateStoreRequest
 import javax.persistence.*
-import kotlin.streams.toList
 
 @Entity
 class StoreDetail(
@@ -51,8 +50,7 @@ class StoreDetail(
     }
 
     fun getSortedStoreImages(): List<StoreImage> {
-        return storeImages.stream()
-            .sorted { o1, o2 -> (o1.id!! - o2.id!!).toInt() }
-            .toList()
+        return storeImages
+            .sortedBy { it.id }
     }
 }
diff --git a/src/main/kotlin/upbrella/be/store/repository/ClassificationWriter.kt b/src/main/kotlin/upbrella/be/store/repository/ClassificationWriter.kt
index 138387bb..b4ce5c62 100644
--- a/src/main/kotlin/upbrella/be/store/repository/ClassificationWriter.kt
+++ b/src/main/kotlin/upbrella/be/store/repository/ClassificationWriter.kt
@@ -2,7 +2,6 @@ package upbrella.be.store.repository
 
 import org.springframework.stereotype.Component
 import upbrella.be.store.entity.Classification
-import upbrella.be.store.entity.ClassificationType
 
 @Component
 class ClassificationWriter(
@@ -15,8 +14,4 @@ class ClassificationWriter(
     fun deleteById(id: Long) {
         classificationRepository.deleteById(id)
     }
-
-    fun saveAll(classifications: List<Classification>) {
-        classificationRepository.saveAll(classifications)
-    }
-}
\ No newline at end of file
+}
diff --git a/src/main/kotlin/upbrella/be/store/repository/StoreDetailReader.kt b/src/main/kotlin/upbrella/be/store/repository/StoreDetailReader.kt
index 292782b6..702f0d85 100644
--- a/src/main/kotlin/upbrella/be/store/repository/StoreDetailReader.kt
+++ b/src/main/kotlin/upbrella/be/store/repository/StoreDetailReader.kt
@@ -17,7 +17,7 @@ class StoreDetailReader(
     @Transactional(readOnly = true)
     fun findByStoreMetaId(storeMetaId: Long): StoreDetail {
         return storeDetailRepository.findByStoreMetaIdUsingFetchJoin(storeMetaId)
-            .orElseThrow() { NonExistingStoreDetailException("[ERROR] 존재하지 않는 가게입니다.") }
+            .orElseThrow { NonExistingStoreDetailException("[ERROR] 존재하지 않는 가게입니다.") }
     }
 
     fun findAllStoresForAdmin(): List<SingleStoreResponse> {
diff --git a/src/main/kotlin/upbrella/be/store/repository/StoreDetailRepository.kt b/src/main/kotlin/upbrella/be/store/repository/StoreDetailRepository.kt
index 936961bd..448d33b4 100644
--- a/src/main/kotlin/upbrella/be/store/repository/StoreDetailRepository.kt
+++ b/src/main/kotlin/upbrella/be/store/repository/StoreDetailRepository.kt
@@ -2,8 +2,5 @@ package upbrella.be.store.repository
 
 import org.springframework.data.jpa.repository.JpaRepository
 import upbrella.be.store.entity.StoreDetail
-import java.util.*
 
-interface StoreDetailRepository : JpaRepository<StoreDetail, Long>, StoreDetailRepositoryCustom {
-    fun findStoreDetailByStoreMetaId(storeMetaId: Long): Optional<StoreDetail>
-}
\ No newline at end of file
+interface StoreDetailRepository : JpaRepository<StoreDetail, Long>, StoreDetailRepositoryCustom
diff --git a/src/main/kotlin/upbrella/be/store/repository/StoreImageReader.kt b/src/main/kotlin/upbrella/be/store/repository/StoreImageReader.kt
index 6ba6c217..d7667993 100644
--- a/src/main/kotlin/upbrella/be/store/repository/StoreImageReader.kt
+++ b/src/main/kotlin/upbrella/be/store/repository/StoreImageReader.kt
@@ -1,5 +1,6 @@
 package upbrella.be.store.repository
 
+import org.springframework.data.repository.findByIdOrNull
 import org.springframework.stereotype.Component
 import upbrella.be.store.entity.StoreImage
 
@@ -8,6 +9,6 @@ class StoreImageReader(
     private val storeImageRepository: StoreImageRepository
 ) {
     fun findById(id: Long): StoreImage? {
-        return storeImageRepository.findById(id).orElse(null);
+        return storeImageRepository.findByIdOrNull(id)
     }
-}
\ No newline at end of file
+}
diff --git a/src/main/kotlin/upbrella/be/store/repository/StoreImageRepository.kt b/src/main/kotlin/upbrella/be/store/repository/StoreImageRepository.kt
index e2d38fbd..3732f4e9 100644
--- a/src/main/kotlin/upbrella/be/store/repository/StoreImageRepository.kt
+++ b/src/main/kotlin/upbrella/be/store/repository/StoreImageRepository.kt
@@ -3,6 +3,4 @@ package upbrella.be.store.repository
 import org.springframework.data.jpa.repository.JpaRepository
 import upbrella.be.store.entity.StoreImage
 
-interface StoreImageRepository : JpaRepository<StoreImage, Long> {
-    fun findByStoreDetailId(storeDetailId: Long): List<StoreImage>
-}
\ No newline at end of file
+interface StoreImageRepository : JpaRepository<StoreImage, Long>
diff --git a/src/main/kotlin/upbrella/be/store/repository/StoreMetaRepository.kt b/src/main/kotlin/upbrella/be/store/repository/StoreMetaRepository.kt
index cdc935f1..b521e5ac 100644
--- a/src/main/kotlin/upbrella/be/store/repository/StoreMetaRepository.kt
+++ b/src/main/kotlin/upbrella/be/store/repository/StoreMetaRepository.kt
@@ -2,10 +2,8 @@ package upbrella.be.store.repository
 
 import org.springframework.data.jpa.repository.JpaRepository
 import upbrella.be.store.entity.StoreMeta
-import java.util.Optional
 
 interface StoreMetaRepository : JpaRepository<StoreMeta, Long>, StoreMetaRepositoryCustom {
-    fun findByClassificationIdAndDeletedIsFalse(id: Long): Optional<StoreMeta>
 
     fun existsByClassificationIdAndDeletedIsFalse(classificationId: Long): Boolean
-}
\ No newline at end of file
+}
diff --git a/src/main/kotlin/upbrella/be/store/service/ClassificationService.kt b/src/main/kotlin/upbrella/be/store/service/ClassificationService.kt
index 521e3ff8..8b05eb7b 100644
--- a/src/main/kotlin/upbrella/be/store/service/ClassificationService.kt
+++ b/src/main/kotlin/upbrella/be/store/service/ClassificationService.kt
@@ -1,6 +1,5 @@
 package upbrella.be.store.service
 
-import org.springframework.context.annotation.Lazy
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Transactional
 import upbrella.be.store.dto.request.CreateClassificationRequest
@@ -12,7 +11,6 @@ import upbrella.be.store.dto.response.SingleSubClassificationResponse
 import upbrella.be.store.entity.Classification
 import upbrella.be.store.entity.ClassificationType
 import upbrella.be.store.exception.AssignedClassificationException
-import upbrella.be.store.exception.IncorrectClassificationException
 import upbrella.be.store.exception.NonExistingClassificationException
 import upbrella.be.store.repository.ClassificationReader
 import upbrella.be.store.repository.ClassificationWriter
@@ -83,4 +81,4 @@ class ClassificationService(
             subClassifications = classifications
         )
     }
-}
\ No newline at end of file
+}
diff --git a/src/main/kotlin/upbrella/be/store/service/StoreDetailService.kt b/src/main/kotlin/upbrella/be/store/service/StoreDetailService.kt
index 1d900149..e612490d 100644
--- a/src/main/kotlin/upbrella/be/store/service/StoreDetailService.kt
+++ b/src/main/kotlin/upbrella/be/store/service/StoreDetailService.kt
@@ -62,10 +62,9 @@ class StoreDetailService(
         val collected = storeDetails.groupBy { it.storeMeta!!.subClassification!!.id }
 
         // 같은 ID끼리 리스트로 모은 것을 StoreIntroductionsResponseByClassification으로 변환
-        val storeDetailsByClassification = collected.entries.stream()
-            .sorted(compareBy { it.key })
+        val storeDetailsByClassification = collected.entries
+            .sortedBy { it.key }
             .map { StoreIntroductionsResponseByClassification.of(it.key!!, it.value) }
-            .toList()
 
         return AllStoreIntroductionResponse.of(storeDetailsByClassification)
     }
diff --git a/src/main/kotlin/upbrella/be/store/service/StoreImageService.kt b/src/main/kotlin/upbrella/be/store/service/StoreImageService.kt
index 57ffbd2b..b97b335d 100644
--- a/src/main/kotlin/upbrella/be/store/service/StoreImageService.kt
+++ b/src/main/kotlin/upbrella/be/store/service/StoreImageService.kt
@@ -1,6 +1,5 @@
 package upbrella.be.store.service
 
-import org.springframework.context.annotation.Lazy
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Transactional
 import org.springframework.web.multipart.MultipartFile
@@ -16,7 +15,7 @@ import upbrella.be.store.repository.StoreDetailReader
 import upbrella.be.store.repository.StoreImageReader
 import upbrella.be.store.repository.StoreImageWriter
 import java.io.IOException
-import java.util.UUID
+import java.util.*
 
 @Service
 class StoreImageService(
@@ -96,4 +95,4 @@ class StoreImageService(
         val splitUrl = url.split("/")
         return splitUrl[splitUrl.size - 2] + "/" + splitUrl[splitUrl.size - 1]
     }
-}
\ No newline at end of file
+}
diff --git a/src/main/kotlin/upbrella/be/umbrella/controller/UmbrellaController.kt b/src/main/kotlin/upbrella/be/umbrella/controller/UmbrellaController.kt
index a725d1d0..5454dabd 100644
--- a/src/main/kotlin/upbrella/be/umbrella/controller/UmbrellaController.kt
+++ b/src/main/kotlin/upbrella/be/umbrella/controller/UmbrellaController.kt
@@ -27,7 +27,7 @@ class UmbrellaController(
                     200,
                     "전체 우산 현황 조회 성공",
                     UmbrellaPageResponse(
-                        umbrellaResponsePage = umbrellaService!!.findAllUmbrellas(pageable!!)
+                        umbrellaResponsePage = umbrellaService.findAllUmbrellas(pageable!!)
                     )
                 )
             )
@@ -46,7 +46,7 @@ class UmbrellaController(
                     200,
                     "지점 우산 현황 조회 성공",
                     UmbrellaPageResponse(
-                        umbrellaResponsePage = umbrellaService!!.findUmbrellasByStoreId(storeId, pageable!!)
+                        umbrellaResponsePage = umbrellaService.findUmbrellasByStoreId(storeId, pageable!!)
                     )
                 )
             )
@@ -54,7 +54,7 @@ class UmbrellaController(
 
     @PostMapping("/admin/umbrellas")
     fun addUmbrella(@RequestBody umbrellaCreateRequest: @Valid UmbrellaCreateRequest?): ResponseEntity<CustomResponse<*>> {
-        umbrellaService!!.addUmbrella(umbrellaCreateRequest!!)
+        umbrellaService.addUmbrella(umbrellaCreateRequest!!)
         return ResponseEntity
             .ok()
             .body(
@@ -72,7 +72,7 @@ class UmbrellaController(
         @RequestBody umbrellaModifyRequest: @Valid UmbrellaModifyRequest?,
         @PathVariable id: Long
     ): ResponseEntity<CustomResponse<*>> {
-        umbrellaService!!.modifyUmbrella(id, umbrellaModifyRequest!!)
+        umbrellaService.modifyUmbrella(id, umbrellaModifyRequest!!)
         return ResponseEntity
             .ok()
             .body(
@@ -87,7 +87,7 @@ class UmbrellaController(
 
     @DeleteMapping("/admin/umbrellas/{id}")
     fun deleteUmbrella(@PathVariable id: Long): ResponseEntity<CustomResponse<*>> {
-        umbrellaService!!.deleteUmbrella(id)
+        umbrellaService.deleteUmbrella(id)
         return ResponseEntity
             .ok()
             .body(
@@ -109,7 +109,7 @@ class UmbrellaController(
                     "success",
                     200,
                     "전체 우산 통계 조회 성공",
-                    umbrellaService!!.getUmbrellaAllStatistics()
+                    umbrellaService.getUmbrellaAllStatistics()
                 )
             )
     }
@@ -123,7 +123,7 @@ class UmbrellaController(
                     "success",
                     200,
                     "지점 우산 통계 조회 성공",
-                    umbrellaService!!.getUmbrellaStatisticsByStoreId(storeId)
+                    umbrellaService.getUmbrellaStatisticsByStoreId(storeId)
                 )
             )
     }
diff --git a/src/main/kotlin/upbrella/be/umbrella/controller/UmbrellaExceptionHandler.kt b/src/main/kotlin/upbrella/be/umbrella/controller/UmbrellaExceptionHandler.kt
index 75353fc7..f1a03e1d 100644
--- a/src/main/kotlin/upbrella/be/umbrella/controller/UmbrellaExceptionHandler.kt
+++ b/src/main/kotlin/upbrella/be/umbrella/controller/UmbrellaExceptionHandler.kt
@@ -1,12 +1,12 @@
-package upbrella.be.umbrella.controller;
+package upbrella.be.umbrella.controller
 
-import org.springframework.http.ResponseEntity;
-import org.springframework.web.bind.annotation.ExceptionHandler;
-import org.springframework.web.bind.annotation.RestControllerAdvice;
-import upbrella.be.umbrella.exception.ExistingUmbrellaUuidException;
-import upbrella.be.umbrella.exception.NonExistingBorrowedHistoryException;
-import upbrella.be.umbrella.exception.NonExistingUmbrellaException;
-import upbrella.be.util.CustomErrorResponse;
+import org.springframework.http.ResponseEntity
+import org.springframework.web.bind.annotation.ExceptionHandler
+import org.springframework.web.bind.annotation.RestControllerAdvice
+import upbrella.be.umbrella.exception.ExistingUmbrellaUuidException
+import upbrella.be.umbrella.exception.NonExistingBorrowedHistoryException
+import upbrella.be.umbrella.exception.NonExistingUmbrellaException
+import upbrella.be.util.CustomErrorResponse
 
 @RestControllerAdvice
 class UmbrellaExceptionHandler {
@@ -19,7 +19,7 @@ class UmbrellaExceptionHandler {
                 .body(CustomErrorResponse(
                         "fail",
                         400,
-                        "이미 존재하는 우산 관리 번호입니다."));
+                        "이미 존재하는 우산 관리 번호입니다."))
     }
 
     @ExceptionHandler(NonExistingUmbrellaException::class)
@@ -30,7 +30,7 @@ class UmbrellaExceptionHandler {
                 .body(CustomErrorResponse(
                         "fail",
                         404,
-                        "존재하지 않는 우산 고유 번호입니다."));
+                        "존재하지 않는 우산 고유 번호입니다."))
     }
 
     @ExceptionHandler(NonExistingBorrowedHistoryException::class)
@@ -41,6 +41,6 @@ class UmbrellaExceptionHandler {
                 .body(CustomErrorResponse(
                     "fail",
                     404,
-                    "사용자가 빌린 우산이 없습니다."));
+                    "사용자가 빌린 우산이 없습니다."))
         }
 }
diff --git a/src/main/kotlin/upbrella/be/umbrella/dto/request/UmbrellaCreateRequest.kt b/src/main/kotlin/upbrella/be/umbrella/dto/request/UmbrellaCreateRequest.kt
index 43a8895f..2d067fe7 100644
--- a/src/main/kotlin/upbrella/be/umbrella/dto/request/UmbrellaCreateRequest.kt
+++ b/src/main/kotlin/upbrella/be/umbrella/dto/request/UmbrellaCreateRequest.kt
@@ -1,4 +1,4 @@
-package upbrella.be.umbrella.dto.request;
+package upbrella.be.umbrella.dto.request
 
 data class UmbrellaCreateRequest (
 
diff --git a/src/main/kotlin/upbrella/be/umbrella/dto/request/UmbrellaModifyRequest.kt b/src/main/kotlin/upbrella/be/umbrella/dto/request/UmbrellaModifyRequest.kt
index 6a8162a2..ebabf6bf 100644
--- a/src/main/kotlin/upbrella/be/umbrella/dto/request/UmbrellaModifyRequest.kt
+++ b/src/main/kotlin/upbrella/be/umbrella/dto/request/UmbrellaModifyRequest.kt
@@ -1,4 +1,4 @@
-package upbrella.be.umbrella.dto.request;
+package upbrella.be.umbrella.dto.request
 
 data class UmbrellaModifyRequest (
 
diff --git a/src/main/kotlin/upbrella/be/umbrella/dto/response/UmbrellaPageResponse.kt b/src/main/kotlin/upbrella/be/umbrella/dto/response/UmbrellaPageResponse.kt
index fb5df57c..cd973fa7 100644
--- a/src/main/kotlin/upbrella/be/umbrella/dto/response/UmbrellaPageResponse.kt
+++ b/src/main/kotlin/upbrella/be/umbrella/dto/response/UmbrellaPageResponse.kt
@@ -1,4 +1,4 @@
-package upbrella.be.umbrella.dto.response;
+package upbrella.be.umbrella.dto.response
 
 
 data class UmbrellaPageResponse (
diff --git a/src/main/kotlin/upbrella/be/umbrella/dto/response/UmbrellaResponse.kt b/src/main/kotlin/upbrella/be/umbrella/dto/response/UmbrellaResponse.kt
index de62f508..9ada544e 100644
--- a/src/main/kotlin/upbrella/be/umbrella/dto/response/UmbrellaResponse.kt
+++ b/src/main/kotlin/upbrella/be/umbrella/dto/response/UmbrellaResponse.kt
@@ -1,4 +1,4 @@
-package upbrella.be.umbrella.dto.response;
+package upbrella.be.umbrella.dto.response
 
 data class UmbrellaResponse (
 
diff --git a/src/main/kotlin/upbrella/be/user/service/BlackListService.kt b/src/main/kotlin/upbrella/be/user/service/BlackListService.kt
index aaacc586..bf01b0bd 100644
--- a/src/main/kotlin/upbrella/be/user/service/BlackListService.kt
+++ b/src/main/kotlin/upbrella/be/user/service/BlackListService.kt
@@ -6,7 +6,6 @@ import upbrella.be.user.dto.response.AllBlackListResponse
 import upbrella.be.user.exception.BlackListUserException
 import upbrella.be.user.repository.BlackListReader
 import upbrella.be.user.repository.BlackListWriter
-import upbrella.be.user.repository.UserReader
 
 @Service
 class BlackListService(
@@ -28,4 +27,4 @@ class BlackListService(
     fun checkBlackList(userId: Long) {
         blackListReader.findById(userId)?.let { throw BlackListUserException("[ERROR] 정지된 회원입니다. 정지된 회원은 이용이 불가능합니다.") }
     }
-}
\ No newline at end of file
+}
diff --git a/src/main/kotlin/upbrella/be/user/service/UserService.kt b/src/main/kotlin/upbrella/be/user/service/UserService.kt
index 8a026363..607289e1 100644
--- a/src/main/kotlin/upbrella/be/user/service/UserService.kt
+++ b/src/main/kotlin/upbrella/be/user/service/UserService.kt
@@ -1,16 +1,20 @@
 package upbrella.be.user.service
 
-import org.springframework.context.annotation.Lazy
 import org.springframework.stereotype.Service
 import org.springframework.transaction.annotation.Transactional
 import upbrella.be.rent.entity.History
 import upbrella.be.rent.service.RentService
 import upbrella.be.user.dto.request.JoinRequest
 import upbrella.be.user.dto.request.UpdateBankAccountRequest
-import upbrella.be.user.dto.response.*
+import upbrella.be.user.dto.response.AllUsersInfoResponse
+import upbrella.be.user.dto.response.KakaoLoginResponse
+import upbrella.be.user.dto.response.SessionUser
+import upbrella.be.user.dto.response.UmbrellaBorrowedByUserResponse
 import upbrella.be.user.entity.BlackList
 import upbrella.be.user.entity.User
-import upbrella.be.user.exception.*
+import upbrella.be.user.exception.BlackListUserException
+import upbrella.be.user.exception.ExistingMemberException
+import upbrella.be.user.exception.NonExistingMemberException
 import upbrella.be.user.repository.*
 import upbrella.be.util.AesEncryptor
 import java.time.LocalDateTime
diff --git a/src/test/kotlin/upbrella/be/config/FixtureBuilderFactory.kt b/src/test/kotlin/upbrella/be/config/FixtureBuilderFactory.kt
index 174d64c0..e4dd5b31 100644
--- a/src/test/kotlin/upbrella/be/config/FixtureBuilderFactory.kt
+++ b/src/test/kotlin/upbrella/be/config/FixtureBuilderFactory.kt
@@ -27,7 +27,7 @@ import java.time.LocalDateTime
 
 object FixtureBuilderFactory {
 
-    val fixtureMonkey = FixtureMonkey.builder()
+    private val fixtureMonkey: FixtureMonkey = FixtureMonkey.builder()
         .objectIntrospector(BuilderArbitraryIntrospector.INSTANCE )
         .plugin(KotlinPlugin())
         .defaultNotNull(true)
diff --git a/src/test/kotlin/upbrella/be/config/FixtureFactory.kt b/src/test/kotlin/upbrella/be/config/FixtureFactory.kt
index eec6d745..3d22db1a 100644
--- a/src/test/kotlin/upbrella/be/config/FixtureFactory.kt
+++ b/src/test/kotlin/upbrella/be/config/FixtureFactory.kt
@@ -7,7 +7,6 @@ import com.navercorp.fixturemonkey.kotlin.giveMeBuilder
 import com.navercorp.fixturemonkey.kotlin.instantiator.instantiateBy
 import upbrella.be.rent.dto.response.HistoryInfoDto
 import upbrella.be.rent.dto.response.RentalHistoryResponse
-import upbrella.be.rent.entity.History
 import upbrella.be.store.entity.StoreMeta
 import upbrella.be.umbrella.dto.request.UmbrellaCreateRequest
 import upbrella.be.umbrella.dto.response.UmbrellaResponse
@@ -78,13 +77,6 @@ object FixtureFactory {
             .sample()
     }
 
-    @JvmStatic
-    fun buildHistoryWithUmbrella(umbrella: Umbrella): History {
-        return fixtureMonkey.giveMeBuilder<History>()
-            .set("umbrella", umbrella)
-            .sample()
-    }
-
     @JvmStatic
     fun buildOauthToken(): OauthToken {
         return fixtureMonkey.giveMeBuilder<OauthToken>()
diff --git a/src/test/kotlin/upbrella/be/docs/common/CustomController.kt b/src/test/kotlin/upbrella/be/docs/common/CustomController.kt
index ca31ffa4..d52f1960 100644
--- a/src/test/kotlin/upbrella/be/docs/common/CustomController.kt
+++ b/src/test/kotlin/upbrella/be/docs/common/CustomController.kt
@@ -15,7 +15,7 @@ class CustomController {
         return ResponseEntity
             .ok()
             .body(
-                CustomResponse<Any>(
+                CustomResponse(
                     "success",
                     200,
                     "요청 성공 메시지",
@@ -29,7 +29,7 @@ class CustomController {
         return ResponseEntity
             .badRequest()
             .body(
-                CustomResponse<Any>(
+                CustomResponse(
                     "fail",
                     400,
                     "잘못된 요청입니다",
@@ -37,4 +37,4 @@ class CustomController {
                 )
             )
     }
-}
\ No newline at end of file
+}
diff --git a/src/test/kotlin/upbrella/be/rent/controller/RentControllerTest.kt b/src/test/kotlin/upbrella/be/rent/controller/RentControllerTest.kt
index 27090a5b..f0e61958 100644
--- a/src/test/kotlin/upbrella/be/rent/controller/RentControllerTest.kt
+++ b/src/test/kotlin/upbrella/be/rent/controller/RentControllerTest.kt
@@ -33,7 +33,7 @@ import upbrella.be.rent.service.ConditionReportService
 import upbrella.be.rent.service.ImprovementReportService
 import upbrella.be.rent.service.LockerService
 import upbrella.be.rent.service.RentService
-import upbrella.be.slack.service.SlackAlarmService
+import upbrella.be.slack.SlackAlarmService
 import upbrella.be.user.dto.response.SessionUser
 import upbrella.be.user.entity.User
 import upbrella.be.user.repository.UserReader
diff --git a/src/test/kotlin/upbrella/be/rent/service/RentServiceTest.kt b/src/test/kotlin/upbrella/be/rent/service/RentServiceTest.kt
index d32f47ed..a6160974 100644
--- a/src/test/kotlin/upbrella/be/rent/service/RentServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/rent/service/RentServiceTest.kt
@@ -28,6 +28,7 @@ import upbrella.be.rent.exception.NonExistingHistoryException
 import upbrella.be.rent.exception.NotAvailableUmbrellaException
 import upbrella.be.rent.exception.NotRefundedException
 import upbrella.be.rent.repository.RentRepository
+import upbrella.be.slack.SlackAlarmService
 import upbrella.be.store.entity.StoreMeta
 import upbrella.be.store.repository.StoreMetaReader
 import upbrella.be.umbrella.entity.Umbrella
@@ -74,6 +75,9 @@ class RentServiceTest {
     @Mock
     private lateinit var conditionReportService: ConditionReportService
 
+    @Mock
+    private lateinit var slackAlarmService: SlackAlarmService
+
     @InjectMocks
     private lateinit var rentService: RentService
 
diff --git a/src/test/kotlin/upbrella/be/slack/service/SlackAlarmServiceTest.kt b/src/test/kotlin/upbrella/be/slack/service/SlackAlarmServiceTest.kt
index a4ce30c1..bcd70bc2 100644
--- a/src/test/kotlin/upbrella/be/slack/service/SlackAlarmServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/slack/service/SlackAlarmServiceTest.kt
@@ -2,6 +2,7 @@ package upbrella.be.slack.service
 
 import org.junit.jupiter.api.Assertions.assertAll
 import org.junit.jupiter.api.Assertions.assertTrue
+import org.junit.jupiter.api.BeforeEach
 import org.junit.jupiter.api.DisplayName
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.ExtendWith
@@ -15,6 +16,13 @@ import org.springframework.http.HttpEntity
 import org.springframework.http.HttpMethod
 import org.springframework.web.client.RestTemplate
 import upbrella.be.config.SlackBotConfig
+import upbrella.be.rent.dto.request.RentUmbrellaByUserRequest
+import upbrella.be.rent.entity.History
+import upbrella.be.slack.SlackAlarmService
+import upbrella.be.store.entity.StoreMeta
+import upbrella.be.umbrella.entity.Umbrella
+import upbrella.be.user.entity.User
+import java.time.LocalDateTime
 
 @ExtendWith(MockitoExtension::class)
 class SlackAlarmServiceTest {
@@ -27,6 +35,64 @@ class SlackAlarmServiceTest {
     @InjectMocks
     private lateinit var slackAlarmService: SlackAlarmService
 
+    private lateinit var rentUmbrellaByUserRequest: RentUmbrellaByUserRequest
+    private lateinit var foundStoreMeta: StoreMeta
+    private lateinit var foundUmbrella: Umbrella
+    private lateinit var userToRent: User
+    private lateinit var history: History
+
+    @BeforeEach
+    fun setUp() {
+        rentUmbrellaByUserRequest = RentUmbrellaByUserRequest(
+            region = "신촌",
+            storeId = 25L,
+            umbrellaId = 99L,
+            conditionReport = "상태 양호"
+        )
+
+        foundStoreMeta = StoreMeta(
+            id = 25L,
+            name = "motive study cafe",
+            deleted = false,
+            category = "category",
+            activated = false
+        )
+
+        foundUmbrella = Umbrella(
+            id = 99L,
+            uuid = 99L,
+            deleted = false,
+            storeMeta = foundStoreMeta,
+            rentable = true,
+            createdAt = LocalDateTime.now(),
+            etc = "etc",
+            missed = false,
+        )
+
+        userToRent = User(
+            0L,
+            "테스터",
+            "010-1234-5678",
+            "email",
+            false,
+            null,
+            null,
+            11L
+        )
+
+        history = History(
+            id = 33L,
+            rentedAt = LocalDateTime.of(1000, 12, 3, 4, 24),
+            returnedAt = LocalDateTime.of(1000, 12, 3, 4, 25),
+            refundedAt = LocalDateTime.of(1000, 12, 3, 4, 26),
+            refundedBy = userToRent,
+            returnStoreMeta = foundStoreMeta,
+            umbrella = foundUmbrella,
+            user = userToRent,
+            rentStoreMeta = foundStoreMeta,
+        )
+    }
+
     @Test
     @DisplayName("우산을 반납하면 Slack 봇으로 잔여 환급 개수와 함께 알림이 전송된다.")
     fun notifyReturn() {
@@ -42,9 +108,10 @@ class SlackAlarmServiceTest {
         ).willReturn(null)
 
         // when
-        slackAlarmService.notifyReturn(1)
+        slackAlarmService.notifyReturn(userToRent, history, 1L)
 
-        val requestEntityCaptor = ArgumentCaptor.forClass(HttpEntity::class.java as Class<HttpEntity<Any>>)
+        val requestEntityCaptor =
+            ArgumentCaptor.forClass(HttpEntity::class.java)
         // then
 
         assertAll(
@@ -59,10 +126,9 @@ class SlackAlarmServiceTest {
             },
             {
                 assertTrue(
-                    requestEntityCaptor.value.body.toString().contains("1")
+                    requestEntityCaptor.value.body.toString().contains("우산 반납 알림")
                 )
-            }// "1"이 포함되었는지 확인 (우산 반납 수)
-
+            }
         )
     }
-}
\ No newline at end of file
+}
diff --git a/src/test/kotlin/upbrella/be/store/service/BusinessHourServiceTest.kt b/src/test/kotlin/upbrella/be/store/service/BusinessHourServiceTest.kt
index 6cfd7ebc..abddacde 100644
--- a/src/test/kotlin/upbrella/be/store/service/BusinessHourServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/store/service/BusinessHourServiceTest.kt
@@ -105,7 +105,7 @@ class BusinessHourServiceTest {
         val updateBusinessHours = mutableListOf<SingleBusinessHourRequest>()
 
         // 이전 데이터와 업데이트 데이터를 생성
-        for (day in DayOfWeek.values()) {
+        for (day in DayOfWeek.entries) {
             businessHours.add(
                 BusinessHour(
                     date = day,
diff --git a/src/test/kotlin/upbrella/be/store/service/ClassificationServiceTest.kt b/src/test/kotlin/upbrella/be/store/service/ClassificationServiceTest.kt
index 38a8959b..9486174d 100644
--- a/src/test/kotlin/upbrella/be/store/service/ClassificationServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/store/service/ClassificationServiceTest.kt
@@ -1,14 +1,13 @@
 package upbrella.be.store.service
 
-import org.assertj.core.api.Assertions.assertThat
 import org.assertj.core.api.Assertions.assertThatThrownBy
 import org.junit.jupiter.api.Assertions.assertAll
 import org.junit.jupiter.api.Assertions.assertEquals
 import org.junit.jupiter.api.DisplayName
-import org.junit.jupiter.api.Nested
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.ExtendWith
-import org.mockito.BDDMockito.*
+import org.mockito.BDDMockito.doNothing
+import org.mockito.BDDMockito.given
 import org.mockito.InjectMocks
 import org.mockito.Mock
 import org.mockito.Mockito
@@ -18,7 +17,6 @@ import upbrella.be.store.dto.request.CreateSubClassificationRequest
 import upbrella.be.store.entity.Classification
 import upbrella.be.store.entity.ClassificationType
 import upbrella.be.store.exception.AssignedClassificationException
-import upbrella.be.store.exception.IncorrectClassificationException
 import upbrella.be.store.repository.ClassificationReader
 import upbrella.be.store.repository.ClassificationWriter
 import upbrella.be.store.repository.StoreMetaReader
diff --git a/src/test/kotlin/upbrella/be/store/service/StoreDetailServiceTest.kt b/src/test/kotlin/upbrella/be/store/service/StoreDetailServiceTest.kt
index dfed4898..cda5490e 100644
--- a/src/test/kotlin/upbrella/be/store/service/StoreDetailServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/store/service/StoreDetailServiceTest.kt
@@ -16,7 +16,6 @@ import upbrella.be.store.entity.*
 import upbrella.be.store.exception.NonExistingStoreDetailException
 import upbrella.be.store.repository.ClassificationReader
 import upbrella.be.store.repository.StoreDetailReader
-import upbrella.be.store.repository.StoreDetailWriter
 import upbrella.be.store.repository.StoreMetaReader
 import upbrella.be.umbrella.service.UmbrellaService
 import java.time.DayOfWeek
@@ -38,15 +37,9 @@ class StoreDetailServiceTest {
     @Mock
     private lateinit var storeDetailReader: StoreDetailReader
 
-    @Mock
-    private lateinit var storeDetailWriter: StoreDetailWriter
-
     @Mock
     private lateinit var businessHourService: BusinessHourService
 
-    @Mock
-    private lateinit var storeImageService: StoreImageService
-
     @InjectMocks
     private lateinit var storeDetailService: StoreDetailService
 
@@ -180,19 +173,6 @@ class StoreDetailServiceTest {
         private val businessHours =
             listOf(monday, tuesday, wednesday, thursday, friday, saturday, sunday)
 
-        private val storeMeta = StoreMeta(
-            id = 1L,
-            name = "협업 지점명",
-            activated = true,
-            deleted = false,
-            classification = classification,
-            subClassification = subClassification,
-            category = "카테고리",
-            latitude = 33.33,
-            longitude = 33.33,
-            businessHours = businessHours
-        )
-
         private val first = StoreImage(
             id = 1L,
             imageUrl = "https://null.s3.ap-northeast-2.amazonaws.com/store-image/filename.jpg"
@@ -203,8 +183,6 @@ class StoreDetailServiceTest {
             imageUrl = "https://null.s3.ap-northeast-2.amazonaws.com/store-image/filename.jpg"
         )
 
-        private val images = setOf(first, second)
-
         private val singleStoreResponse = SingleStoreResponse(
             id = 1L,
             name = "협업 지점명",
@@ -580,9 +558,9 @@ class StoreDetailServiceTest {
 
         given(storeDetailReader.findByStoreMetaId(storeId))
             .willReturn(storeDetail)
-        given(classificationReader.findByIdAndType(request.classificationId!!, ClassificationType.CLASSIFICATION))
+        given(classificationReader.findByIdAndType(request.classificationId, ClassificationType.CLASSIFICATION))
             .willReturn(classificationUpdate)
-        given(classificationReader.findByIdAndType(request.subClassificationId!!, ClassificationType.SUB_CLASSIFICATION))
+        given(classificationReader.findByIdAndType(request.subClassificationId, ClassificationType.SUB_CLASSIFICATION))
             .willReturn(subClassificationUpdate)
         given(storeMetaReader.findById(storeId))
             .willReturn(storeMeta)
diff --git a/src/test/kotlin/upbrella/be/store/service/StoreMetaServiceTest.kt b/src/test/kotlin/upbrella/be/store/service/StoreMetaServiceTest.kt
index 1826aaba..707b2307 100644
--- a/src/test/kotlin/upbrella/be/store/service/StoreMetaServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/store/service/StoreMetaServiceTest.kt
@@ -2,8 +2,11 @@ package upbrella.be.store.service
 
 import org.assertj.core.api.Assertions.assertThat
 import org.assertj.core.api.Assertions.assertThatThrownBy
-import org.junit.jupiter.api.*
 import org.junit.jupiter.api.Assertions.assertAll
+import org.junit.jupiter.api.BeforeEach
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.api.Nested
+import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.ExtendWith
 import org.mockito.BDDMockito.*
 import org.mockito.InjectMocks
@@ -19,7 +22,6 @@ import upbrella.be.store.dto.response.StoreMetaWithUmbrellaCount
 import upbrella.be.store.entity.*
 import upbrella.be.store.exception.DeletedStoreDetailException
 import upbrella.be.store.exception.EssentialImageException
-import upbrella.be.store.exception.NonExistingStoreMetaException
 import upbrella.be.store.repository.*
 import upbrella.be.umbrella.entity.Umbrella
 import upbrella.be.umbrella.exception.NonExistingUmbrellaException
diff --git a/src/test/kotlin/upbrella/be/umbrella/controller/UmbrellaControllerTest.kt b/src/test/kotlin/upbrella/be/umbrella/controller/UmbrellaControllerTest.kt
index 2f607419..fee3b67a 100644
--- a/src/test/kotlin/upbrella/be/umbrella/controller/UmbrellaControllerTest.kt
+++ b/src/test/kotlin/upbrella/be/umbrella/controller/UmbrellaControllerTest.kt
@@ -116,7 +116,7 @@ class UmbrellaControllerTest : RestDocsSupport() {
         }
 
         val pageable = PageRequest.of(0, 5)
-        given(umbrellaService.findUmbrellasByStoreId(storeId.toLong(), pageable))
+        given(umbrellaService.findUmbrellasByStoreId(storeId, pageable))
             .willReturn(umbrellaResponseList)
 
         val info: MultiValueMap<String, String> = LinkedMultiValueMap()
@@ -213,7 +213,7 @@ class UmbrellaControllerTest : RestDocsSupport() {
                 .sample()
 
             // 여기서 컨트롤러에 예외 핸들러를 설정
-            mockMvc = RestDocsSupport.setControllerAdvice(initController(),
+            mockMvc = setControllerAdvice(initController(),
                 UmbrellaExceptionHandler()
             )
 
@@ -244,7 +244,7 @@ class UmbrellaControllerTest : RestDocsSupport() {
         @Test
         fun success() {
             // given
-            val id = FixtureBuilderFactory.buildLong(1000)
+            val id = buildLong(1000)
             val umbrellaModifyRequest = FixtureBuilderFactory.builderUmbrellaModifyRequest()
                 .sample()
 
@@ -289,11 +289,11 @@ class UmbrellaControllerTest : RestDocsSupport() {
         @Test
         fun existingUmbrellaUuid() {
             // given
-            val id = FixtureBuilderFactory.buildLong(1000)
+            val id = buildLong(1000)
             val umbrellaModifyRequest = FixtureBuilderFactory.builderUmbrellaModifyRequest()
                 .sample()
 
-            mockMvc = RestDocsSupport.setControllerAdvice(initController(),
+            mockMvc = setControllerAdvice(initController(),
                 UmbrellaExceptionHandler()
             )
 
@@ -319,11 +319,11 @@ class UmbrellaControllerTest : RestDocsSupport() {
         @Test
         fun notExistingUmbrellaId() {
             // given
-            val id = FixtureBuilderFactory.buildLong(1000)
+            val id = buildLong(1000)
             val umbrellaModifyRequest = FixtureBuilderFactory.builderUmbrellaModifyRequest()
                 .sample()
 
-            mockMvc = RestDocsSupport.setControllerAdvice(initController(),
+            mockMvc = setControllerAdvice(initController(),
                 UmbrellaExceptionHandler()
             )
 
@@ -354,7 +354,7 @@ class UmbrellaControllerTest : RestDocsSupport() {
         @Test
         fun success() {
             // given
-            val id = FixtureBuilderFactory.buildLong(1000)
+            val id = buildLong(1000)
             willDoNothing().given(umbrellaService).deleteUmbrella(eq(id))
 
             // when & then
@@ -380,8 +380,8 @@ class UmbrellaControllerTest : RestDocsSupport() {
         @Test
         fun notExistingUmbrella() {
             // given
-            val id = FixtureBuilderFactory.buildLong(1000)
-            mockMvc = RestDocsSupport.setControllerAdvice(initController(),
+            val id = buildLong(1000)
+            mockMvc = setControllerAdvice(initController(),
                 UmbrellaExceptionHandler()
             )
 
@@ -492,7 +492,7 @@ class UmbrellaControllerTest : RestDocsSupport() {
         @Test
         fun notExistingStoreMeta() {
             // given
-            val storeId = FixtureBuilderFactory.buildLong(1000)
+            val storeId = buildLong(1000)
             mockMvc = setControllerAdvice(initController(), StoreExceptionHandler())
 
             willThrow(
diff --git a/src/test/kotlin/upbrella/be/umbrella/service/UmbrellaServiceTest.kt b/src/test/kotlin/upbrella/be/umbrella/service/UmbrellaServiceTest.kt
index b213d113..3fc7549c 100644
--- a/src/test/kotlin/upbrella/be/umbrella/service/UmbrellaServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/umbrella/service/UmbrellaServiceTest.kt
@@ -22,7 +22,6 @@ import upbrella.be.rent.service.RentService
 import upbrella.be.store.entity.StoreMeta
 import upbrella.be.store.exception.NonExistingStoreMetaException
 import upbrella.be.store.repository.StoreMetaReader
-import upbrella.be.store.service.StoreMetaService
 import upbrella.be.umbrella.dto.request.UmbrellaCreateRequest
 import upbrella.be.umbrella.dto.request.UmbrellaModifyRequest
 import upbrella.be.umbrella.dto.response.UmbrellaResponse
diff --git a/src/test/kotlin/upbrella/be/user/integration/UserIntegrationTest.kt b/src/test/kotlin/upbrella/be/user/integration/UserIntegrationTest.kt
index 91042110..3bef1212 100644
--- a/src/test/kotlin/upbrella/be/user/integration/UserIntegrationTest.kt
+++ b/src/test/kotlin/upbrella/be/user/integration/UserIntegrationTest.kt
@@ -475,7 +475,8 @@ class UserIntegrationTest : RestDocsSupport() {
             .andExpect(status().isOk)
 
         // then
-        assertThat(em.find(User::class.java, 1L)).isNotNull
+        val user = userRepository.findAll().firstOrNull()
+        assertThat(user).isNotNull
     }
 
     @Test
diff --git a/src/test/kotlin/upbrella/be/user/service/BlackListServiceTest.kt b/src/test/kotlin/upbrella/be/user/service/BlackListServiceTest.kt
index 09633684..4460b73b 100644
--- a/src/test/kotlin/upbrella/be/user/service/BlackListServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/user/service/BlackListServiceTest.kt
@@ -14,10 +14,8 @@ import org.mockito.junit.jupiter.MockitoExtension
 import upbrella.be.user.entity.BlackList
 import upbrella.be.user.exception.BlackListUserException
 import upbrella.be.user.repository.BlackListReader
-import upbrella.be.user.repository.BlackListRepository
 import upbrella.be.user.repository.BlackListWriter
 import java.time.LocalDateTime
-import java.util.*
 
 @ExtendWith(MockitoExtension::class)
 class BlackListServiceTest {
@@ -90,4 +88,4 @@ class BlackListServiceTest {
         // then
         verify(blackListWriter, times(1)).deleteById(blackListId)
     }
-}
\ No newline at end of file
+}
diff --git a/src/test/kotlin/upbrella/be/user/service/UserServiceTest.kt b/src/test/kotlin/upbrella/be/user/service/UserServiceTest.kt
index ee11501b..6719fdad 100644
--- a/src/test/kotlin/upbrella/be/user/service/UserServiceTest.kt
+++ b/src/test/kotlin/upbrella/be/user/service/UserServiceTest.kt
@@ -31,15 +31,15 @@ import java.time.LocalDateTime
 @ExtendWith(MockitoExtension::class)
 class UserServiceTest {
 
-    @Mock
-    private lateinit var userRepository: UserRepository
-
     @Mock
     private lateinit var blackListReader: BlackListReader
 
     @Mock
     private lateinit var blackListWriter: BlackListWriter
 
+    @Mock
+    private lateinit var userRepository: UserRepository
+
     @Mock
     private lateinit var userReader: UserReader
 
diff --git a/src/test/kotlin/upbrella/be/util/AesTest.kt b/src/test/kotlin/upbrella/be/util/AesTest.kt
deleted file mode 100644
index 0b062146..00000000
--- a/src/test/kotlin/upbrella/be/util/AesTest.kt
+++ /dev/null
@@ -1,52 +0,0 @@
-package upbrella.be.util
-
-import org.assertj.core.api.Assertions.assertThat
-import org.junit.jupiter.api.DisplayName
-import org.junit.jupiter.api.Test
-import org.springframework.beans.factory.annotation.Autowired
-import org.springframework.boot.test.context.SpringBootTest
-
-@SpringBootTest
-class AesTest @Autowired constructor(
-    private val aesEncryptor: AesEncryptor,
-){
-    @Test
-    @DisplayName("복호화 테스트")
-    fun testDecrypt() {
-        // given
-        val plainText = "Hello World!"
-        val encryptedText = aesEncryptor.encrypt(plainText)
-
-        // when
-        val decryptedText = aesEncryptor.decrypt(encryptedText)
-
-        // then
-        assertThat(decryptedText).isEqualTo("Hello World!")
-    }
-
-    @Test
-    @DisplayName("Null을 암호화하는 경우 출력도 Null")
-    fun testEncryptNullInput() {
-        // given
-        val nullString : String? = null
-
-        // when
-        val encryptedText = aesEncryptor.encrypt(nullString)
-
-        // then
-        assertThat(encryptedText).isNull()
-    }
-
-    @Test
-    @DisplayName("Null을 복호화 하는 경우 경우 출력도 Null")
-    fun testDecryptNullInput() {
-        // given
-        val nullString : String? = null
-
-        // when
-        val decryptedText = aesEncryptor.decrypt(nullString)
-
-        // then
-        assertThat(decryptedText).isNull()
-    }
-}
diff --git a/src/test/resources/application-test.yml b/src/test/resources/application-test.yml
index 8228cec0..27c61b88 100644
--- a/src/test/resources/application-test.yml
+++ b/src/test/resources/application-test.yml
@@ -1,16 +1,17 @@
 spring:
-  config:
-    import: "classpath:application.properties"
   datasource:
-    url: ${DATABASE_URL}
-    username: ${DATABASE_USERNAME}
-    password: ${DATABASE_PASSWORD}
-    driver-class-name: com.mysql.cj.jdbc.Driver
+    url: jdbc:h2:mem:testdb;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE
+    username: sa
+    password:
+    driver-class-name: org.h2.Driver
   jpa:
+    hibernate:
+      ddl-auto: create-drop
     properties:
       hibernate:
+        dialect: org.hibernate.dialect.H2Dialect
         format_sql: true
-        show-sql: true
+        show_sql: true
 
 logging:
   level:
@@ -19,5 +20,4 @@ logging:
         SQL: DEBUG
         type:
           descriptor:
-            sql: trace
-
+            sql: TRACE