Umgeni Autohaus are total cheats - beware

On December 4, I bought an Audi A4 at Umgeni Autohaus. The service was good and the staff was very friendly. Before paying for the car, I requested its service book and Kriben told me he was gonna call Audi for that. I requested for a spare key, he said he was gonna have it couriered as it was still with the previous owner. I have been pestering him for these. And on one occasion when I was parking the car on a pavement, I noticed a lot of noise underneath and I told him. The car would shake violently when on neutral and cut. I told him and he said its service and i requested the service book as he had previously told me service was done on intervals. He ran away, not answering my calls until i had to call the owner Jason I sent Jason all the Whatsapp conversations between myself and Kriben. He advised that he was not at the office and will call me when he gets there. I called him the following day and he said he was from a Dr and will call me the next day...he didn't till I called him and he asked what is it that I need him to do for me, I told him about the service and referred him to my Whatsapp messages on his phone. He promised to have a look at my file and come back to me. It was Friday last week and since then I've been dropping him texts and he wouldn't bother himself responding. The car has got lots of faults, no spare key, idling, service and no service book. Kindly come to my rescue.