Message guest and apologise. Have a look at other local options so you can recommend somewhere else and more likely to agree to cancel. Don’t get booking.com to do it for you as it will charge a relocation fee. Only guest can cancel so to initiate.
Extranet
Reservations
Reservations Details Page
Right Pane, Request To Cancel
Choose option 2, submit
Wait for guest to receive email with action to confirm
this booking number was for a stay on 5/18 for 1 night for 2 rooms, there is some type of payment error, that very well could be on the hotel's part, I needed
Message guest and apologise. Have a look at other local options so you can recommend somewhere else and more likely to agree to cancel. Don’t get booking.com to do it for you as it will charge a relocation fee. Only guest can cancel so to initiate.