Vechile not in good condition

on the 20th of September I purchased a Land Rover Discovery 3 from Gusteau's Auto in Durban (Shelly Beach Marine Drive). I drove the car to our local town on the 28th of September 2015 when the car started giving me problems with the gears. I then called Gusteau's Auto and asked to be assisted but with no luck as they said I was the one who damaged the car. I then opted to take it to Land Rover Nelspruit where it was diagnosed and and the gentleman who assisted me there said it was a FACTORY ELECTRONICAL FAULT, I had to pay R500.00 for that service as Gusteau's refused to help me. I am currently paying for the car still but am not drivinig it which I feel isn't fair. Still no assistance from Gusteau's Auto even after several times of calling them with their empty promises, last time I drove my car was on the 28th September 2015.