1 yassine ayouch #Urgent i can't host *** my appartement is already. booked i. want to cancell ***'s booking 11 BrookAve Then simply cancel it Cancelling the (over)booking as a Partner Message the guest , explain overbooked, system should not have allowed it or COVID19 local restrictions prevent you from hosting. etc Be smart about which excuse you use, and do not over do it, no waffle or padding. When you message the guest finish off by saying , once you initiate the cancelation they will receive notification to acknowledge via a confirm link in the message. And that their prepayment (if any) will then be auto processed for full refund by Booking.com, only once they take that action. Of course if you can offer some detail on next availability, if any. and offer to confirm dates they may send on. On the reservation details page on right pane bottom , click Request Cancel , choose option 2, and wait for guest to confirm the notification by clicking the action in it.