******* by audi east rand

I took my car audi to by east rand mall the Central locking system was not working ,they diagnosed that there was a water pump problem. I paid R18000 to have both problems a month lateri took it back because it was making a rattling sound. A diagnosis a was given and i paid R6500 to have the rattling sound removed. A diagnosis for cause of the sound was made and i paid R6500. When i fetched my car i was told the rattling sound is still there but a different problem was fixed with the money i had paid. I raised enquiries of why i didnt get what i paid for and to date there are no answers. I want a refund or the rattling sound gone as that is what i paid for