Hi Helen3.
I took your suggestion and called Customer Service. They were very helpful.
Apparently, a guest who cancels can submit unlimited refund requests for the same booking within 30 day of the check-in date.
I told the Customer Service that is ridiculous and has to change.
The ability to submit an official refund request should be limited to 2 times.
I assume Customer Service reached out to the canceled guest. I received a "Ticket is Closed" notice from them, and have not heard back with any more refund requests from the guest. Case Closed but it was very annoying.