Dishonest sales person

I bought a car from Webuycars in Midstream. After looking at the vehicle inside the store facility, I asked the salesperson Winstone if I can take it for a test drive. He drove the car outside of the warehouse. We change seats while the vehicle was idling. I notice the auto start stop light flushing, I asked him about it. He said he switch it off cause he didn't like riding with it. I accepted his explanation. After driving the car, I asked him if the vehicle was in an accident, he verbalize that not as far as he can see or know. I bought the car. Driving home, I notice that if you start the car it gives a message auto start stop fault. I also notice when I opened the rear door that the plastic trimming was clued previously and that the car was in an accident at that area. When I went to fetch the papers of the vehicle on Thursday 28th January, I report the problem. Till now no one followed up on my complain.