No care about client service only client money

I have an old reliable 2003 Mazda Etude that was involved in an accident end June 2017. Following the required processes the claim was approved and repairs to be done by their elected service provider. They estimated the repair time to be 10 working days allocating a few days allowance for sourcing parts. It has being 30 working days since and the car in still in the workshop. Why??? because they mechanic cannot get the car started. News flash Momentum - you need to change your mechanic. Now I would think after putting a client through so much off additional costs and inconvenience the least they can do is arrange car hire until my car is repaired or ensure that they deliver my car in a roadworthy condition immediately. But all I get is feeble excuses and how I should have taken car hire with my insurance. Surely if I had taken car hire with them then my car will have being ready within 7 working days. All this frustrations after me making efforts to pay my premiums on time - their service stinks. Now they want to deliver the car to me as it is as they now have diagnosed that the car had a problem with starting before the accident - what a load of **** - how did it manage to get itself involved in an accident?? I would be very wary of these guys.