I have communicated with them through this email:
support@globalcasinoservices.zendesk.com
However….
***Please note that we do not have access to modify your reservation in any way, including cabin upgrades, waiving penalties, changing room numbers, names, casino offers, ship or sail dates, and more.
For any such requests, we kindly ask you to contact your travel professional or the casino reservations call center directly. They will be able to assist you with your reservation request(s).***