No pride in superior customer experience and service. Just a slogan with no meaning. Pathetic

I have a Mercedes C250d 2016. It has been giving me issues with coolant issues and I took it to Mercedes Benz in Ermelo( De Wit motor) and they did a diagnosis and told me there was a wiring issue and the coolant pump wasn’t getting enough power and charged me +-9600 rands and after that the problem persisted and they said the ECU and circulation pump needs changing because it’s not communicating well. They gave me quotation was about R42700.00. They carried out the work but the car still has the same issue and now they’ve changed and are saying the car has a blown head gasket. The same issue that I took the car to them for has changed from wiring to ECU to head gasket with a new quotation of 176K. At this point I guess they’re just playing a chase game and I can say very ***********. I took up the issue with Mercedes Benz South Africa and was in communication with a lady by the name Joyce Makhutle who without considering the facts I had placed before her simply dismissed and said from her engagement with the workshop the car had been to another workshop and therefore they can’t take responsibility. My argument is I took the car to Benz with the very same issues and they did their own diagnosis and did repairs based to their own recommendations but the issue remains and if they say it’s the gasket now then it means they misdiagnosed the car in the first place and whatever they did on the car was unnecessary and therefore they should refund me my money so I can repair my car.