Worst customer service.

I am very unhappy with their customer service. My car has been with them for over a month and they claim that they can’t get parts from their dealer. I think they keep our cars at their premises longer at their premises for dishonest reasons. Can’t find vw parts for over a month? First they pretended that they didn’t have my car in their yard. Secondly they pretended to not have received authorisation from my insurance for the repairs now they can’t find parts for a Vw car in the entire country? I wish our insurances would allow us to take our cars to reliable repair shops that we know of.