The first time I signed in with Apple in my app, I received the full Create an account for <app> using your Apple ID flow. However, I was not able to see and save the email and fullName fields. In all subsequent logins after original sign up, only the uid is given by Apple. This is expected behaviour, see

Unfortunately, for this account it does not show the original login flow after this step, but just the regular Log in screen, for when you are a returning user.

Other steps I added:

• removing the record from the Authentication screen in the Users table in Firebase.
• disabling, deleting and re-enabling the Apple Sign in in Firebase
• flutter clean
• flutter pub cache repair
• deleting the app from the test device, rebooting test device and rebuilding from Android Studio.
• removing and re-adding Sign in with Apple in XCode via Runner -> Signing & Capabilities
• logging in with my Google Sign in and then logging out so it clears my shared preferences:

SharedPreferences preferences = await SharedPreferences.getInstance();
await preferences.clear();

Env info:

username@devicename appname % flutter doctor -v
[✓] Flutter (Channel stable, 3.3.8, on macOS 12.6.1 21G217 darwin-x64, locale en-NL)
    • Flutter version 3.3.8 on channel stable at /Users/username/Development/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 52b3dc25f6 (4 weeks ago), 2022-11-09 12:09:26  0800
    • Engine revision 857bd6b74c
    • Dart version 2.18.4
    • DevTools version 2.15.0

[✓] Android toolchain - develop for Android devices (Android SDK version 32.0.0)
    • Android SDK at /Users/username/Library/Android/sdk
    • Platform android-33, build-tools 32.0.0
    • Java binary at: /Applications/Android Studio.app/Contents/jre/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 11.0.13 0-b1751.21-8125866)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 14.1)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 14B47b
    • CocoaPods version 1.11.2

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2021.3)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from: