Sign In with Apple Integration Issue - "Sign-Up not completed" Error

I'm experiencing an issue with Sign In with Apple integration in my React Native Expo app (Bundle ID: com.anonymous.TuZjemyApp). Problem Description: When users attempt to sign in using Sign In with Apple, they successfully complete Face ID/password authentication, but then receive a "Sign-Up not completed" error message. The authentication flow appears to stop at this point and doesn't return the identity token to my app. Technical Details: Frontend Implementation:

Using expo-apple-authentication. Requesting scopes: FULL_NAME and EMAIL App is properly configured in app.json with:

usesAppleSignIn: true Entitlement: com.apple.developer.applesignin

Backend Implementation:

Endpoint: POST /api/auth/apple Using apple-signin-auth package for token verification Verifying tokens with audience: com.anonymous.TuZjemyApp Backend creates/updates user accounts based on Apple ID

Question: I'm not sure why the authentication flow stops with "Sign-Up not completed" after successful Face ID verification. The identity token never reaches my app. Could you please help me understand:

What might cause this specific error message? Are there any additional Apple Developer Portal configurations required? Could this be related to app capabilities or entitlements? Is there a specific setup needed for the app to properly receive identity tokens?

I set up provisioning profiles, and added Sign in with Apple as a capability and still it doesn't work.

Thanks for the post. React Native?

You should check with the support resources provided by the 3rd party to get assistance with their software.

Unless another developer in the forums has experience with the third-party and can provide assistance.

Albert Pascual
  Worldwide Developer Relations.

Sign In with Apple Integration Issue - "Sign-Up not completed" Error
 
 
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