Bad service

I am so disappointed in m-sure and their service to me when claiming for short fall cover, it's been almost 2 weeks now and I have sent through all the documents requested except for the assessor's report which I have made them aware multiple times on email, that my insurance advised that it is an internal document that they don't give to external parties. Proof of loss has been sent amongst the documents requested and settlement portion that was done by my insurance but still my claim is not finalized and there is no way forward now. Next, I got SMS that said if I don't provide requested document my claim will be cancelled.