Short end of the stick

I have been having a bad experience with Momentum Insurance since I was involved in an accident with one of their clients in October 2019,the insurer has since sidelined my 3rd party claim because of problems it has with its client,problems which according to my understanding are admin related.My question is why as a 3rd Party claim must I suffer the same outcome on my claim as their client?It has been 2 month since the accident and I still don't know where I stand with them.Bare in mind their client is at fault.