Problem with old Play Games account

[wantroba]

Recently, an app user contacted me reporting a problem. After thorough evaluation, I discovered that the app didn't return the await GameAuth.signIn(); call, nor did it throw an exception.

I asked him to change the settings in Play Games to always ask for the player profile when logging into the app. When he opened the app and selected the profile he'd had for many years, the app wouldn't progress and would get stuck on the call I mentioned above await GameAuth.signIn();. When he opened the app and clicked "Cancel," that is, without selecting any profile, the app worked without issues (since I allow the user to play without being logged into a Play Games account). I asked him to create another profile in Play Games, and the await GameAuth.signIn(); call executed correctly, and everything worked as expected.

I couldn't debug it because he's a user who kindly performed the steps I requested remotely. I'll leave his phone settings:

Samsung Galaxy A32
Android 13 (SDK 33)
Play Games account approximately 15 years old.

Edit:
I assumed the app was stuck on this call await GameAuth.signIn();, but there's a chance it's stuck somewhere else. So I'll paste the full code for that part here:

try {
        if (!(await GameAuth.isSignedIn)) {
          await GameAuth.signIn();
        }
        firebaseAuthPlayerId = await _firebaseAuthSignIn();
        displayName = await GamesServices.getPlayerName();
        gameServicesId = await GamesServices.getPlayerID();
      } catch (e) {
        FirebaseUtils.recordError(e, StackTrace.current);
      }

static Future<String?> _firebaseAuthSignIn() async {
    try {
      String? uid;
      if (Platform.isAndroid) {
        final authCode = await GameAuth.getAuthCode(
            "{mycode}.apps.googleusercontent.com");
        if (authCode != null) {
          final userCredential =
              await FirebaseAuth.instance.signInWithCredential(
            PlayGamesAuthProvider.credential(serverAuthCode: authCode),
          );
          uid = userCredential.user?.uid;
        }
      } else if (Platform.isIOS) {
        final userCredential = await FirebaseAuth.instance
            .signInWithCredential(GameCenterAuthProvider.credential());
        uid = userCredential.user?.uid;
      }
      return uid;
    } catch (e) {
      FirebaseUtils.recordError(e, null);
      return null;
    }
  }

[theLee3]

Was this user able to successfully sign in to GPG for your app previously, or was this a first time user of your app experiencing the issue from the start?

[wantroba]

Was this user able to successfully sign in to GPG for your app previously, or was this a first time user of your app experiencing the issue from the start?

This was the first time this user had downloaded my app. He'd never used it before.

I know this is a difficult situation to replicate and try to figure out where the potential error might lie 🙃. If you find this impossible, you can close this bug report, as I resolved this situation directly with the user. I only decided to flag it here in case this is a truly major issue that needs to be resolved.

[theLee3]

Thanks @wantroba. This could certainly be tricky. It's hard to imagine it being something other than a platform issue, as we have no instruction to handle an old account differently than any other.

I will keep it open for now with hopes of doing some digging soon to see if there is any chance it's something we need to address.