@Andee1
That is odd they are just notifying you? Normally Airbnb sends pymt 24hrs after check-in? What did Airbnb CS say when you contacted them? Did the guest do a credit card chargeback?
When You'll Receive Paymouts for Monthly Stays
https://www.airbnb.com/help/article/285
...For reservations that are 28 nights or more, we collect payments in monthly installments.
- We’ll charge your guest for the first month upfront and release that first payment to you 24 hours after their scheduled check-in.
- Upcoming payouts are released to you on a monthly basis, based on the check-in date, for the duration of the reservation.
- Once payouts are released by Airbnb, how long it takes you to get your money depends on your payout method’s processing time. Find the processing times for payout methods.