Google Play Games failing with specific user

Question

I'm using Flutter and games_services. First of all, all the setup is done. SHA1 keys are properly setup in Google Play Console and Google Cloud:

• Debug (this key is generated when Android Studio is intalled)
• Release (the key we generate manually)
• Signing (in GPC, setup, app signing). This one is also marked as "Use this credential for new installs".

I double checked all of them by also running ./gradlew signingReport

When I tried with my wife's account, it worked on emulator and real device. But when trying with my user it only works on emulator. On real device (Redmi Note 10 Pro, but I don't think this is not relevant) it fails.

Future<void> showLeaderboards() async {
    try {
      await Leaderboards.showLeaderboards(
          androidLeaderboardID: androidLeaderboardId);
    } catch (error) {
      debugPrint(error.toString());
    }
  }

Future<void> showAchievements() async {
    try {
      await Achievements.showAchievements();
    } catch (error) {
      debugPrint(error.toString());
    }
  }

These show: 4: The user must be signed in to make this API call. Sometimes SIGN_IN_REQUIRED (but sound similar). The user is already logged in and I see the Google's popup with my user. The problem comes when calling any other method apart from signIn.