diff --git a/backend/src/zango/apps/appauth/auth_backend.py b/backend/src/zango/apps/appauth/auth_backend.py
index 6d4e9f99..d3a78178 100644
--- a/backend/src/zango/apps/appauth/auth_backend.py
+++ b/backend/src/zango/apps/appauth/auth_backend.py
@@ -23,7 +23,9 @@ class AppUserModelBackend(ModelBackend):
     def authenticate(self, request, username=None, password=None):
         if request and request.tenant.tenant_type == "app":
             try:
-                user = AppUserModel.objects.get(Q(email=username) | Q(mobile=username))
+                user = AppUserModel.objects.get(
+                    Q(email__iexact=username) | Q(mobile=username)
+                )
                 pwd_valid = user.check_password(password)
                 if pwd_valid and user.is_active:
                     return user