When we went in January there had been many changes all the way around on Carnival.
We keep passports even though we are US citizens and don't need them to cruise. Just good security.
On the limited information in your post I have to agree that Carnival may be right. BUT again I'm sure there is a lot more to the story. They have tightened down dramatically lately though and I have to say I'm glad. Sorry for the problems but it sounds like it could have happened on any cruise line. Debbie