Shocking Renault service

I took my vehicle into Sterling Renault shortly after they had done a service. My aircon had packed up. They sent it to another provider in Herm**** who said there was a crack in the aircon pipe that could be welded. I took it to him a week later. When I returned to collect the vehicle he said the crack had happened because a wire leading to the lights had come loose and was resting on the pipe. My wife and I took it back to Sterling Renault to ask the manager about this. When he was told about the issue he became very defensive, rude and unpleasant. Eventually he walked off shaking his head and muttering. I lodged a complaint online at Renault South Africa. I received a mail the next day- impressive! I was told I would have a response shortly. I waited a week and then mailed them to ask what wzs going on. Received an apology and was told the issue was " being escalated" and I would have a response by 12 on Monday. It was Friday. A week after that I mailed again. Reply came that the agent had been out of the office. I answered and said that was an unacceptable reply. I waited another week and was then sent a reply that I could do one of 2 things. Go to Sterling Renault western cape, or take the car to a Renault dealer to evaluate the problem. The latter would be at my expense. I pointed out this was unacceptable. I was not prepared to spend more money on something which almost a month later could not be resolved. Plus the problem was with Sterling Renault in the first place. Why had no ospoken to them in the first place. I asked to be put in touch with the manager.No response. I phoned. I was initially put in touch woth the *********** agent but then got a manager. She did email back, but essentially said they could do nothing. So I spent R3500 repairing something which I believe could be a direct result of incompetence. We will never know for sure. I told them I had owned my Renault for over 9 years and was very happy with it. I was looking to buy a new vehicle and had been looking at another Renault. Now I will not buy one. I am so thoroughly disappointed with Sterling and Renault South Africa. Very poor service.