Dotsure great, then not-so-great

Our pet dog was insured with petsure - the accident plan. Initially Dotsure was very prompt, polite and prepared to help. Our dog had injured her back and we once again took her to the vet as her back legs were not working. While at the vet, he discovered a lump which turned out to be cancerous. She eventually had an operation, then sadly passed away a couple of months later. I tried to claim for the visit to the vet for her back legs, and did not claim for subsequent visits, for the operation or for the euthanasia. Dotsure repudiated the appointment for her legs, then said they would look again. I have not heard anything else from them - not a phone call or an email or anything. Very disappointed.