BAD SERVICE and a moth LATER MY CAR IS STILL NOT FIXED

i took my car in for an assessment on the 25 April and I was quoted for the part and assured that it I buy this part the car will be fixed , was even given a reference of a customer with a similar problem that went through the same process 5 years ago and has never returned since , I was quoted R 32 000 and assured that as soon as I made the payment the part will be ordered and in 3 days I will get my car, I went home and took their assurance to heart and on Monday the 29 April made the payment , Thabiso Bill was the person who was assigned to work with me through this, the part got there 4 days later and was never informed I had to call Thabiso to find out about this and there he gave ne excuses of him being busy when the part arrived on Friday, I have received the worst service from Thabiso Bill who never contact me and never puts anything on paper , when I asked he actually was annoyed that I wrote and email asking for feedback which I think is why I received this service from him.everytime I called to get progress they inform me of something that I need to buy and quote me again adding their labour every time a month later my car is still there and not fixed and they give me different names of parts needed every time , I have spoken to the manager John Leith but still no joy , I have taken enquired about the part they require and found that they not related to the problem , may I please ask for your assistance as I have lost all hope and do not have a clue on where to go from here.