@Paul-and-Lynn1 Did you ask the guest to cancel the inquiry?
I'm not really sure how that works if you pre-approve an inquiry. Once it enters the stage of the payment being verified, it might be in some kind of limbo neither the host nor guest can alter.
You could contact CS and ask them to look at the message fron the guest that they are no longer coming, and ask them to unblock your calendar.
And was this an inquiry or a booking request?