Unhappy with my rejected claim

My car was damaged by water in the DME (inside the control unit). As a result of this my car engine couldn't start. I notified my insurance about this and I was told to tow in my car to an authorized dealer to get it diagnosed and obtain a quotation. This was done and I submitted a claim form as well as the quotation to the insurance by 14 March 2016.<br> <br> The insurance then appointed an assessor to go to the dealer (JSN Motors). On 22 March I was told my claim had been rejected because of damage not being water but electrical related (as per the assessor). This did not make sense to me as BMW had already confirmed to me earlier that the damage was caused by water.<br> <br> I then contacted BMW to confirm what the insurance was saying. BMW still insisted and up to today still insists the damage was caused by water. Communication, including pictures confirming this was water damage were sent to the insurance by myself and BMW. The same assessor maintained his earlier decision. Case was then assigned to a senior assessor who also rejected my claim stating BMW was not helpful. I don't think it is fair to say BMW has not been helpful as they did not only send emails but also called the insurance.