Answer: Reschedule for a later class or find an opening.
Explanation: You don't just say no especially if you're managing a resort. There are other ways to go about it. Most places offer multiple classes to suit everyone who stays. Rescheduling for a later time may prove beneficial if the person was late to sign up at the start. You could also see if there was more room in the class as having more in would be beneficial in terms of revenue.