Subpar customer service and exceedingly poor communication

Booking was made with the dealer VW Kempton Park, and the date was confirmed, but my car was not attended to, and there was no information from them regardless of the booking slot; I had to repeatedly ask for an update. Now that the insurance company approved the quote and authorized the job, I had to fight for the car to be serviced again and struggle to get a turnaround time. I was only recently told that the car is fine but that the engine knock is still present, and that the car is going to be stripped again. I am still waiting for an update or communication to date. The service is so poor that I have to involve third parties and escalate the issue.