Poor quality service

My car was damaged in an accident and towed away the same day. I had to call for feedback instead of them updating me regarding my car just to find out that my car was not in the correct place. It took them a week to get my car to the correct place for assessment. When the assessor finally sent the damage report to me he advised that they would only be fixing the right side of the car as he advised that the other damages was old damages. My car was perfectly fine before the incident also note that I had provided images that shows that my car was surrounded with bricks... When I had asked about the repairs to the windscreen he advised me that the crack was an old crack as it had dust in the chip so I advised that obviously it would have dust in it because the car was moved from place to place for the week. When I had asked about the gearbox being assessed he advised me that the car has to be sent away for an internal report regarding damages to the gearbox. I find that this is very unprofessional because all the pictures, statements and explanations was provided and yet I am being told that the damages to my car is old damages. He also advised that my car had previously been crashed into so I advised him that kingprice had repaired that damaged bumper... My question is now... What exactly am I paying for if this is the service that I am getting??? Nobody told me that my car wasn't where it's supposed to be... Deadlines that were given were never met... No feedback provided effeciently... I am being told that the damages to my car are old damages.... What's the use of even having insurance???!!!