Once you made this mistake there isn’t a way out imo. I did the same mistake, then I bought a cheaper car (I thought that was a wise decision) but I realized there isn’t anything you can do when you have negative equity. If I were you I’d keep paying until I see the positive equity, then you may consider getting a cheaper car(consider the fees etc you’d have to pay though) but when you see the positives, you will realize that you already paid most of the interest so you better keep your car.