Bad service

My car was involved in an accident on 4.12.14 and was sent to Farbers for repairs by Dial Direct insurance. For the whole of December I was told that they were busy every time when I called. I had to hire cars in the meantime. I was going to get my car back second week in Jan 2015 but at that time I was told that work still needs to be done. I eventually got my car back mid Feb.I picked up things that I was not happy with and had my car checked out the colour was out, untidy workmanship and a used tyre in my boot and brand new spare was on the car. The tyre was not damaged in the accidentan so I suspeect something else happened to my car while it was there, hence long long time taken. I informed the insurance and an assessor checked the car togethrer with Rayden, Farbers regional manager and it was back with Farbers. I askde Rayden to investigate what happened and he promised to give me a report in 2 days, I haven't heard from him ever since. The car was there for three weeks and I checked it at the assessor's 2 weeks ago. There were still some issues including the tyre and I did not take the car. Another 2 weeks went by, still no word from Farbers and the car is still with them