Complaint against Comprehensive Claims Service

Our *** ********** I want to complain about the bad service i received from the above insurance. Their client drove into my car and i made the claim. Because i was claiming as a third party my claim was not settled it was rejected, i dont think there was investigatiions done.Their driver admitted liability at the scene but the insurance rejected me saying i am the liable party which is not true. They just want to make saving by rejecting my claim,their case law is not relevant to the claim i made.