If you are using iOS SDK versions 3.14.4 to 3.14.13 and you are using the SignInWithApple of the KakaoGameSDK
If you log in to Apple from that version, there will be a 503 error when you log in, so you need to upgrade to version 3.14.14 or higher.
If you are using an iOS SDK version 3.13.1 or earlier and you are using Kakao Friend List
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