MMU MOTORS

I bought a car from MMU MOTORS. On the day I received my car I wasn't given a contract. A month later when I got it I saw that the car was overbooked. The car I bought is R290 000 from other dealers but MMU sold me that car for R340 000. I'm currently paying R6000 for a car that worths R4700 monthly installment. I tried to talk to them and they were rude. The bank financing the car (MFC) doesn't want to help me. I tried to contact MIOSA they also told me that they can't help me and I should go to the lawyers.