You have obviously have not read the crusie contract you agreed to upon booking your cruise, eiterh that or you simply ignored it.
Here ya go!
6c) Itinerary Deviation: The Guest agrees that the Carrier has the sole discretion and liberty to direct the
movements of the vessel, including the rights to: proceed without pilots and tow, and assist other vessels
in all situations; deviate from the purchased voyage or the normal course for any purpose, including,
without limitation, in the interest of Guests or of the vessel, or to save life or property; put in at any
unscheduled or unadvertised port; cancel any scheduled call at any port for any reason and at any time
before, during or after sailing of the vessel; omit, advance or delay landing at any scheduled or advertised
port; return to port of embarkation or to any port previously visited if the Carrier deems it prudent to do so;
substitute another vessel or port(s) of call without prior notice and without incurring any liability to the
Guest on account thereof for any loss, damage or delay whatsoever, whether consequential or otherwise.