Dishonesty by dealership

I have an issue with Modern Autohaus in regards to a 1 Series 118I that I purchased in May 2017. On the 28th March 2018 when I was taking my bag out I discovered it was wet, I place my bag on the floor of the rear seat. Upon checking I discovered that the mat was soaking wet, I immediately contacted the sales person to enquire what could be the cause. He couldn't give me a response. on Monday 16 April 2018 the same thing happened, the mat was soaking wet. I took my vehicle to Best Auto in Rustenburg to have it checked out. On the 17th I received a call from Best Auto that the discovered that water seeps in through the right rear door. I asked how that is possible and that is when I discovered that the vehicle had been to the panel beaters in April 2017, a month prior to me purchasing it.

I again contacted the salesperson to ask him about it and he said there had been an accident and that the right rear door had been replaced. I further asked him why I wasn't informed of the matter and he couldn't give me a response. I contacted the sales manager and explained my issue, as he was driving, he requested that I send him my ID number in order for him to investigate. An hour later he called me and said that he went through my contract and said I had signed for the car and I knew what I was signing for a car with a replaced door. I informed the sales manager that I was not informed and I would not have bought the car if I had been told that the car had been in an accident. I also told him that I am not comfortable with the car anymore because they had not been honest about the state of the car and I didn't want it anymore. I subsequently hung up on him because he kept on insisting that I signed for the car knowing about the door. He called me again, this time around he offered to trade in my car and get me a new one. I informed him that I am not willing to get into a new contract based on their dishonesty.