Sometimes they don't have the excursions for a specific cruise available. For instance, my upcoming Grandeur cruise still shows "not available" when I try to pull up the excursions for our cruise. Yours may not be available until later on this year.
However you can see what is offered at each port by going here
and looking at your ports. Just bear in mind that things might change by the time your cruise is ready to go. Go to a port and then look on the right for "learn more" and the link for tours at that port.