I regret the day I bought a car from Hyundai

My car broke down as I was driving in R27 enroute to Langebaan. To cut the story short my car was taken to Hyundai Milnerton on the 31st of March 2015. I was advised that the battery was faulty, they needed to replace it to do any further test. I gave them the go ahead. They phoned me the morning to explain why the need to replace the battery. I gave them an instruction to stop everything, they quoted me just over R1000.00 for the battery. They replaced my battery even though I told them not to and I had to pay because they refused to take it back. I don't even know what happened to the old one because they took it as well. I am very disappointed with their service and will not recommend anyone I know to buy cars from them.