Claim delays

We have been struggling for months to have a claim sorted. My father has been diagnosed with dementia and it has been months of back and forth requiring extra documents . Everything has been provided . Then comes more info, sorry we cannot pay out the original amount as indicated there is now a change on the clause and its a different amount! My parents are still paying the premium while this unresolved claim is being looked at. This is really putting a financial strain on my parnts. For many years they have been old mutual clients whee it is to the point that they want to cancel all their policies because of the stress they have to go through. This claim has been in since october 2023. Disgracefull