We had ours unexpectedly blocked and we were just using it for a "Login with Google" button. The only explanation was the vague "You did something against our terms and conditions." We hadn't done anything. Our use case is nothing beyond the "Login with Google" button.

We opened a case to appeal asking for more details or a review. Meanwhile, we're scrambling to implement some kind of workaround for our users that log in with their Google account.

And then early the next day, we get the email that our appeal was granted. Just need to be sure we follow the terms and conditions in the future.

I guess it could have been worse but still a bit of a slap in the face.