Crashed car during service

My car was booked in for a service on 13 April. After the service a driver took my car out and crashed the front end. A courtesy car, below standard, was lent to me for what supposed to be a 2-3 week job to repair my car. After numerous emails and phone calls, the persons responsible never returned with any information regarding the current state or delivery date of my vehicle. 22 days later, and with a representative on my behalf investigating the situation, I finally had a response that work had NOT EVEN BEGUN on my vehicle and it would take another 3 weeks to repair!!! I was also emailed a \vehicle loan form"by Audi to pay R5000 deposit on the courtesy car! This has been the WORST service experience I have ever had and refuse to use this centre again"