Bad service

What bad service since that I’m receiving from Hyundai to. I’ve send the car for service in a week my have problems. The car is not powerful now they tell me they did not pick that fault before on service day now I have to pay R28000 to replace something that was not reported before , they telling now after 2 times coming to them telling them something is wrong after the service. What makes me more angry no 1 calls me and update about what happening. I have to take Uber to Hyundai to check this is second time they this to me