Hyundai goes back on their word

On the 31st of July I bought a Hyundai 130i premium from Somerset West branch. On the 14th I took the vehicle for a service and they informed me that the wheel allignmnet was out and because of that the tyres was worn and needs replacement, and advised that I need to go back to the dealership for them to sort out. I went to have the tyres checked and they contacted Tramyn the manager at Hyundai to inform him of the issue at hand. He confirmed that he will raise an order for new tyres the following Monday. On Monday he phoned me saying that he cannot replace the tyres but will pay for the alignment. I explained to him that the alignment was out upon buying the car and the tyres was worn because of that. I am extremely unhappy with the fact that the tyres was a pre existing issue and he went back on his word by not replacing the tyres. I feel that they need to be held responsible for the tyres and the alignment at their own cost. In the mean time I have had to put on two tyres before I embarked on a trip because it wasn't safe driving like that. I had to cover the cost of that from Goodhooe tyres myself. I am still not happy with this and want it resolved as soon as possible.