The guy(Conner) that I talked to at the big box store called Holland and the first person he talked to to add the promo said it couldn’t be done so he called back and spoke to someone else who did do it. At first I was going to loose my shipboard credit of $200 but in the end they just took $25.
It’s all in who they talk to. If you don’t like the first answer hang up, call again and talk to someone else or have them ask to speak to a supervisor.
Conner was great ,l was on the phone with him for over an hour but he was persistent and got it done! Good luck and keep trying because gratuities add up to a lot and in my case it is a 24 day cruise.