Cancellation of contract

I bought a car from Pro-Quick Motors on 17 February 2015 and it gave problems from the second week after being bought. It was taken to them so many times to fix the problems instead it was not fixed. They just cleared the errors. Finally, I got the car to be diagnosed and thereafter, provided them with the list of problems that they need to attend to, but even that did not help. On the 30 April 2015 engine malfunctioning sign appears on the cluster and it could not start. On Friday, 1 May 2015 it was taken back to Pro-Quick and I had to pay R850 to be towed (which was not paid back to date). Afterwards, I negotiated with them to cancel the contract and/or provide me with a different vehicle of the same value (without mechanical problems). However, to date they are not prepared to assist me. The car is still in their possession and I am still continuing with my monthly instalment to MFC. The sales rep is not willing to provide me with the contact details of the dealership owner. Below is the contact details of sales rep:<br> <br> Mr Eddie Mbonani<br> ***<br> ***<br> <br> Your assistance will be appreciated.<br> <br> Regards<br> <br> Jane Mabena<br> ***<br> ***<br> ***<br>