@Kathy39
If the guest has to cancel because of "extenuating circumstances", this procedure could lead to a full refund (which also include the Airbnb fees):
https://www.airbnb.com/help/article/1339/how-do-i-file-an-extenuating-circumstances-claim
If it does not work out for the guest, you can refund him manually by choosing the cancelled reservation from your list of reservations and click : sent or receive money , an option on the pulldown menu when clicking the "three dots" at end of line.
Best regards,
Emiel