We have had a couple of claims. One was for lost luggage and had no problem at all.
The other involved a very minor accident on board with a bill of about $80, from the physician onboard. We had cruise insurance and they told us that even though Medicare would deny the claim, our cruise insurance could not process our claim until we received a rejection from Medicare. Well long story short, it has now been over two months and we are still waiting for our denial. Sometimes you just have to hang in there and keep after them!!