I know that it’s crazy, but let me explain.
I believe, that for the time that Season 2 spans, Clay is suffering from split personality disorder.
Hannah is a projection of Clay’s mind, which means that talking to her is just him talking to his own mind. Hannah is not giving him any new information, just reacting to it. Every time he argues with her, he is arguing with his own mind. I know it’s an abrupt ending to an explaination, but there’s really nothing else to say. Hannah is her own personality in Clay’s mind.