Need for speed unbound dlc bug

just bought need for speed unbound and the latest Audi pack. Basically been scammed. I received the Audi s5 and changed a few parts on it. When I go to lower the car, the lowering slider is not there and my car disappeared. I’ve tried everything and it still happening to this particular car, which I have paid for! Another thing that happens is when I go to performance parts, everything is showing up as tyres and the game completely crashes, I have been forced to sell the car as it’s bugging my game. I want my money back or the problem fixed along with the car! I’m on Xbox series s, literally a brand new one so it’s not my console just this poor excuse for a game.