Same fault over and over. Wasting time and money

It all started last year December when I first visited Samuels with the issue on my vehicle. I told them what problem I was experiencing and then done the relevant check, told me I shouldn't worry car will be fixed. I left the car with them for about 3weeks, and in the end paid up to R25k for the repairs. I did not mind at first because I had the reassurance that my problem was fixed for good. Not even a week later I experienced the same problem, so I was told to take it back. I did and they tried to tweek what ever they could. I when out on work for a few months and left my car standing in my garage. Came back and reminded them that I am still experiencing the same problem as before, I went back then scanned and said it's a different issue, and guaranteed this time the car will be 100%. With hesitation I took out an additional R8 000 to fix this other problem. To my surprise the exact following day, the same issue had resurfaced. Highly upset I phoned in and Informed them of the situation. They sounded surprised and I could not understand how could I have trusted such a company with my car especially after spending well over R35 000 on the repairs. They recently took the car back and I'm now being slapped with another bill of R31 000. I'm so disappointed that such a reputable company is playing games with my time and money. This would possibly be the 5/6th time in 6months I've had to revisit Samuels Service Centre and still today my problem is not solved, R35k later and still expected to pay another R31k for further repairs. It's either I look like a fool to these people or they do not know their job. Tried to call head office but no answer, that's why I decided to voice my grievance on this platform. So disappointed. They should have told me if they could not fix the vehicle initially.