Worst service

I arranged for an avis car to be picked up at 16:00 from a panelbeater where my vehicle was fixed. By 16:30 no one from avis had arrived. Between 16:30-17:00 I phoned them 6 times to find out what was happening as I was already late for a meeting. By 17:00 they said I should leave the car at the panelbeater and they will pick it up in the morning. The next day I receive a phone call to say that there is damage to the vehicle which I will be liable for. There was no damage to the vehicle when I left it. I lodged a complaint with them, but still they deducted R1350 from my credid card. I have attempted to contact them but with no response. This is totally unacceptable. No one from avis was there at 16:00 to assess any damage as there was none. Any damage to the vehicle must have been from their employees