I know this thread is fairly old, but the issue still exists. On that note, I'm frustrated because Apple enforces the use of their sign in solution on anyone who wants to include other social sign in services such as a Google or Facebook. Sign in with Apple is probably the most unsupported sign in service available. Terrible documentation, lack of SDKs for multiple languages and issues such as the issue described in this thread are all evidence of this.
dcrivl
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