If you are top heavy on your car what is the best solution to get out from under this?

Yes, the company is supposed to credit your debt with the amount they can recover by reselling the vehicle, less the cost of that sale, but you will likely not see a benefit from that. Negotiate with the lender, or try to make a sale on your own, choose which is better for you. Just remember, you signed a contract to pay a certain amount and, barring are-negotiated contract from the lender, you owe that amount.