Denting my car and not answering the phone

My vehicle went in to Mc Carthy to fix a software issue. When I got home after getting my car back a day late I noticed a dent in the body above the passenger door. (something that wasn't there before I took the car in, and I'm pretty sure that kind of damage was not unavoidable from their side). Since it was late I called the ext day to inform them, but they told me to call the following day. I've now called 14 times in the course of the day, and the phone has only been answered 3 times. Twice I was routed to the person I needed - but he didn't answer, and one the phone was merely picked up and put down again.