Unhappy with customer service

I took a Hollard Bond Protection in 2009.In2010.I had cancer in my neck. I never claimed for the 6 months I was off work. As I thought it was to soon. So in 2018 I had multiple strokes due to the radiotherapy of the cancer treatment I had. I decided to put a claim in to Hollard for the bond protection. They said the claim was declined due to the original policy for the bond protection laps in 2018 before my stroke and the new policy I took out in 2018 would not cover my claim as it was to soon. They said I could go to the ombudsman if I was unhappy with their decision but write to their own complaints department and promised I would get my own personal go to person who is going to look into my complaint and get back to me. So far I have heard nothing back from them. They don't pick up the phone when I call It seems to me that they waiting for my time to be able to complain to the ombudsman. This has been going on since last year September when I 1st sent in my original claim.