I'm having this issue also and received this error from email from Airbnb 3 days ago. Apparently they've hid my listing 30 days ago but didn't give me any notification that they did so, only a final email that they were deactivating the listing and that it is my PMS software to blame, which I am using Hostaway. I haven't heard back from Hostaway on the issue in two days either. My assumption is that Airbnb is correct and it is an issue with Hostaway, because my listing has been hidden on VRBO as well.
This is the email from Airbnb. Very frustrating to know this has been an issue for over a month now and no one has told me about it. Airbnb, VRBO or Hostaway.
30 days ago, we hid one or more of your listings on Airbnb from guests because they did not have up to date calendar availability. In particular, a large percentage of booking attempts for dates marked as available for your listing(s) were rejected by your software system. Since the issue has not been resolved in 30 days, we are deactivating your listings. You will not receive any further bookings from these listings until they are reactivated and their availability is up to date.) Accordingly, we have unlisted the listing(s). Please resolve the issue and republish the listing to make them available.