Bad customer service.

I've never experienced such a bad customer service since I started having car insurance. I had an incident with my vehicle, as usual I phoned my insurance and notify then about the incident. They arranged the towing service to get my car towed. Problems started when they had to authorize, I was given countless reasons for the delay which I ended up with getting it sorted. They authorized and the guys started working on the vehicle. The day came which I had to go get my vehicle. On arrival the first thing I checked was the certificate from Audi South Africa which authorize the panel beaters to work on their vehicles, I didn't see or get it. Then I realized something is wrong. I took my car on the 4th of March 2019, on the 24th March 2019, the bottom engine cover came out while I was driving due to poor work performance from that car repairer who worked on my vehicle. After checking what was the problem I noticed that wrong *****s was used to mount the bottom engine cover which was the cause of it to come out, and it has caused a lot of damage, even the left fender liner came out when the bottom cover get loosen and was also broken. Isn't it that insurers have a list of authorized body repairers forms car dealers so that they know whom to work with in the case of accidents.