Used car problems

Bought a used car from GWM Boksburg. When I test drove the car it had a wheel wobble and they said they would fix it. I've taken it back twice to fix the same problem and other problems I have noticed. All they have been able to do is change a fuse and a globe, and on top of that drove around 230kms and used half a tank of petrol. They have ignored my emails and when I try tell them the problem still exists. Very disappointed in this ******* service received from them and that the car was falsely advertised.