Upgrade to iOS SDK 3.15.0 or later
The Facebook SDK has been updated in KakaoGameSDK module. So the Facebook client token must be set in info.plist when using Facebook login through KakaoGame Facebook module.
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
...