Claim/repairs taking more than 2months

I had an accident and my car was taken for assessment by Discovery on the 29/12/2014. Until now 16/02/2015 they are still going through the process to repair it. My main problem is that the repairer that they chose cannot get the parts for the car and they say it's not their problem and therefore i had to return the courtesy car. Whose problem is it? Overall the process has been a terribl experience- they dont provide feedback or response on issues. i can say i have spent more than R1000 in phone calls from making international calls. From towing the car to assessment and then to repairer it took more than 3 weeks. This is a poor insurance service provider and i used to recommend it to people before i actually made a claim.