I am fairly certain it is a auto dialer gone awry at some cruise line selling scam or it was in the past. Who knows who is paying for this so-called service now?
There are programs that make calls for "businesses" or other entities who use the phone services to sell or scam. I was offered one of these things once and after careful consideration of 30 secs said no way do I want any part of that mess...
Ignore the calls since there is nothing else that can be done short of filling a complaint with your local phone service provider.
I'm registered on the National Do Not Call List and this number called, and my smart phone showed the call as coming from Chicago, IL. An automated message said press 1 to talk to someone about a cruise, and 2 to be added to their do not call list. I pressed 1, and immediately started into a rant about how their call was illegal, I was on the National Do Not Call List and demanded to talk to their legal department. The gentleman on the other end said "**** you" and then I received a pre-recorded message that my number had been added to their DNC list. I called the number back and it said the number was unavailable.