I need the Guest cancel the reservation

Good morning/evening,

I got a reservation at 20:11 where the Guests asked for a crib and a dog. Both are accepted free of charge but we need to anticipate the check out at 9:30 instead of 11AM because the preparation of the crib. The Guest answered at 21:43 that 9:30 was not possible since they have a 1 year old baby. I replied at 22:00 that we might accept later than 9:30 depending on next Guest arrival schedule. I did not get any answer and at about 22:30 pushed the button for requesting to cancel the reservation due to the Guest incompatibility. Is it possible to clear the booking calendar? The reservation number is 3837446051.

Thank you and best regards, Valentina