I bought a used car here, first off I was supposed...

I bought a used car here, first off I was supposed to be the one financing the car and my dad co-signing the guy who did our paperwork flipped it.. Secondly he told me not to worry about the license plate that he'd take care of it.. I still don't have one and no one will pick up or reply to our calls. Except one time but the guy just said to wait a few more days and that it would be in the mail. Still no license plate, I am willing to go a pick one up but no one is responding to us!