I sold a car, now I’m being sued On January 19 of this year I sold a car for…

I sold a car, now I’m being sued
On January 19 of this year I sold a car for $200 to private party who had seen it on the internet.

Yesterday I was served a subpoena at work stating that
the defendant (myself) owes $3000 to the plantiff
who is not the person that I sold it to. In fact they are a complete stranger whom I have never seen or met.
He is suing me for Fraudulent Automobile Sale; Recission of Contract & Damages. The buyer who’s name and address I was given is no where to be found.
I have a bill of sale signed and dated by the buyer
along with old papers from the car. I endorsed the title but however, neglected to send a Release of Liability form to the DMV.

Where do I stand leagaly?

Auto Purchase from private party I’m giving a private party a certified check…

Auto Purchase from private party
I’m giving a private party a certified check for their used vehicle. Before I get title they must go to their finance company and pay off their loan to get clear title. What should I do to ensure compliance with the terms of our contract? Is a simple bill of sale enough protection? Would it be adequate to have a notarized bill of sale? Thank you.