So are we to understand that when your prophet did this, he was wrong ? That he is not part of your religion ? How exactly does your argument work ? The islami

So are we to understand that when your prophet did this, he was wrong ? That he is not part of your religion ? How exactly does your argument work ? The islamic prophet killed people for apostacy. That's a fact, confirmed by both islamic and non-islamic historical sources. In fact he massacred an entire city for that. So answer the simple question : was that wrong ? Is it okay to kill individuals or massacre cities for apostacy ? If he was wrong, then is there any islamic religion at all ?