Failed Customer service

I had such a bad experience with this company for almost 6 months - my car went in for repairs just for me to discover that it's been standing for over two weeks without anything been done to it, even through they indicate they are busy repairing it and have majority of the parts. I discovered that the car is not worked on and that they have only ordered the additional parts a week after they took my car in, which resulted in they not finding parts in time. Still they never communicated this and I was under impression my car will be fixed within given period of two weeks. I had so much fights with them and they never wanted to accept responsibility and the fact that they were treating me unfairly and without dignity. Finally when the parts came, they fixed it, but then discover other parts also needed to be replaced, another month of waiting just to discover that the parts now need to be ordered from France. During this period I used their courtesy vehicle which was helpful but would have costs me for usage an arm and leg if I continued using it over December 2019 period. Final repairs was done in January 2020, and reported that there were now strange noises coming form the brand new aircon system they replaced but to today they claim its wear and tear and even the insurance now have issues in repairing this. Before the repairs this problem was never their with the broken aircon, a new system installed and its causing problems. I took it for diagnostic which indicated a problem with it, but they send me to another company for second opinion. Air con pressure valve is damaged, and they say they cant replace it - isn't this part of the aircon system supposedly to be replaced?'I am angrily disappointing with the service i got from both my Insurance and panelbeaters. In future i will not make use of them or refer anyone to them. I must tell you my personal opinion is that as a client I felt very dishonored and disrespected in how they treated me in relation to other clients (there is a race service issue). They really need to step up their game when it comes to service all clients equally.