<human>: I stupidly decided to sell my old car myself back in 2011.  I looked up online everything I needed to do to transfer the title over to the guy who purchased it and downloaded some documents for us both to sign.  We met up, signed the paperwork, he gave me cash and I gave him the pink slip and that was it.  I mailed the release of liability to the DMV and I thought we were all squared away.

A few months later I got a red light violation in the mail. I called and told them I didn't own the car and told the DMV about it and to be honest I don't remember what happened, but I assumed everything was taken care of because I never heard anything from them about this issue.

Fast forward to a month ago (4 years later) - my drivers license was about to expire so I went down to the DMV to renew it and they said I couldn't renew it until I paid the violation which is $775.  I don't have the money for that and I absolutely don't want to pay his violation.  

Here's the problem - I have no proof that I ever sold the car...I can't find the paperwork, apparently the DMV doesn't keep any records like that and I don't know the VIN for the car.  I do have the license plate number, but I don't know how useful that will be.  

What can I do to fight this?

Can you provide a brief rundown of the text in within 3 sentences?
<bot>: Got a ticket for a car I sold, want to fight it but have to proof. My license is being held until the situation is resolved.