Altavista Auto Center, L.L.C.

I purchased a car from these people and I am disabled and loss my job and my place to live due to my home burnig and being sent to a shelter to live. I have no job, extremely limited income which is my SSI I receive in the amount of $710 a month and I can not afford this car so I have not been able to make payments on the car. The car has a lock box on it wich they give you a code to enter each week in order to start and drive the car when you make a payment but the payments are too high for me and I have numerous times contacted the company and explained to them that I want to return the car because I can not pay the payments and they wont take the car back and now the car is just sitting here unable to be driven because I have not made payments on it. I have called them and expliained to them that I need to return the car and they wont take it back. They claim that I own the car and they want me to keepit or else they will have to take me to court. I have no insurance on it anymore and they still want me to continue to make payments on it and keep it even though I have tried t return it numerous times. I hhave told them I cant afford it . What should I do?