@Laura2592
I have had this happen a few times and, on this one, I need to stick up for Airbnb. The guest has said to me they are having trouble with paying, I have got onto CX and asked them to facilitate the reservation payment and they have. They have taken care of it and the next thing, I get a booking confirmation.
Airbnb will reach out to the guest, I have found that where money is concerned Airbnb will move heaven and earth to make sure a booking does not escape them!
Cheers......Rob