I recently purchased a car and the car company is saying i couldnt be financed for

[misscelebritybarbie]

the car and they told me to bring the car back cause the finance company could not finance the car but when i got to the car lot the said it was mine with all the legal documents attached with the car && i was approved for a car off the showroom floor they took all my info and everything saying i was approved i signed everything thinkin as if the car was mines being that i traded in my old car for the new one now they are sayin if i dont return the car that was given to me they will press grand theft auto charges i need help please i set out for a new car not to go to jail.....