When I go to my Airbnb listing (searching as if I'm a guest) I notice that the dates that I am booked are not blocked off on the calendar. However, when I put in the dates and then request to book it will say "This place is no longer available."
I have had a lot of issues with my listing myself since the new 2024 Summer Update was released. My listing completely disappeared. And I have lost 241 reviews today - lots of other hosts report the same issue. So it is probably a technical issue you are having as well. Apparently CS is working on getting the issues fixed.