Bad request, message: Value for 'source_lang' not supported.

[ymotongpoo]

I installed v1.1.1 and tried the feature. However, though I ran the DeepL: Translate command, I keep getting error dialog saying:

Bad request, message: Value for 'source_lang' not supported.

My extension setting is as follows:

    "deepl.formality": "less",
    "deepl.tagHandling": "off",
    "deepl.splitSentences": "1",
    "deepl.translationMode": "Replace",
    "deepl.defaultTargetLanguage": "JA",
    "deepl.defaultSourceLanguage": "EN-US",