diamond car insurance

My accident happened quite late (thankfully I was already at home otherwise I would have been hysterical) and was given 3 wrong numbers by Diamond customer service before being passed to Admiral as their claims team work later than Diamond ! I was then given different information from the customer service advisor's on several occasions. My car is being written off (not Diamond's fault but they are no help whatsoever), I've got to pay my excess even though it's not my fault, I can't claim for ...