Car livery doesn't change

Car livery cannot be changed, i bought a car from luxury autos, when i first checked it out and took it for a test drive it was silver painted without any stickers or liveries, i bought the car and the girl that worked there told me to come back in 24h for the paper work, i came back next day and when i recieved the car it had some livery on it and i cannot get it off, every other mod on the car works but the livery change doesnt