“Sign in with Apple” works without any issues when using Auth0 Dev Keys (aka blank Client ID) alongside my Apple Developer’s Team ID, Client Secret Signing Key, and Key ID. However, when I add my Client ID (Apple’s Service IDENTIFIER) the Sign-In always fails with “Sign Up Not Completed” (see attached image).
I have exhausted all resources to try to resolve this issue but without avail.
Please advise how to go about debugging and resolving this issue.