If you do see free play shown in the Onboard Credits section as suggested above, you can call Princess to find out the rest of the details for your offer. Some are discounted cruises only, some include a free cabin. My offers have stopped by the way so I'm thinking that those of us who received them for the first time during the pandemic only got them temporarily so they could fill the ships. I have had the discounts for years and still have that so I'm satisfied with that.