Ripp offs!

I am being ********** by this company. I had issues with my car which showed and "hill start assist" error and I took the car to get fixed. They advised that the issue is the computer box so a new one has to be bought. The invoice cost me 31k and my insurance only covered 2k for a computer box. I made a plan to get the money and paid them. I got my car back and within 2 weeks, I started seeing a "engine hazard" error. I took the car back and they said they fix it. A few weeks donw the line the issue happened again, took the car back and they said they cleared the error and the car is fine. Two weeks after, the initial issue that happened in Jan happened again - showing the "hill start assist"error and the car was making sounds. We took the car back, now they say the the timing chain, injector and spark plugs needs to be replaced. The invoice is 31k! They clearly did not fix the car the first time, cos if they did I would not be getting the same error. They claim that it's not associated to the replacement of the computer box....how convenient. I would not recommend anyone to use their services. They are ripping people off and deliberately ensure that they car is not fully fixed so you can come back again and pay.