@Dan14741 It doesn't solve your immediate issue, it is advice that can prevent it from happening again. You aren't the only host who's gotten shafted like this on last minute bookings.
Airbnb, if they fail to collect payment from the guest, either because of some glitch, or because the guest's credit card was maxed out or invalid, or whatever, always just tells the host essentially, "too bad".
Although they insist on dealing with all the payments, they take no responsibility if the guest's payment doesn't go through.
Sorry this happened to you, but it would be a waste of your time to pursue this, you'll get nowhere.