public void ChangeLogin(string text, IOnCompleteListener c) { FirebaseUser user = FirebaseAuth.Instance.CurrentUser; if (user != null) { UserProfileChangeRequest.Builder profileUpdates = new UserProfileChangeRequest.Builder(); profileUpdates.SetDisplayName(text); UserProfileChangeRequest updates = profileUpdates.Build(); user.UpdateProfile(updates).AddOnCompleteListener(c); } else { throw new Exception("Current user is null"); } }