Hello @Kelly2364
Definitely agree with @Zheng49 advice - don't do anything your end without involving CS first and your idea of delisting to reenlist later will not work as Airbnb will consider this as a duplicate listing and will suspend the new one.
If you have a long term guest then Airbnb's long term cancelation policy kicks in which means that the guest have to give you a months notice and need the host to approve if the notice falls under the 30 day notice. A guest can shorten their stay with no host approval if they give that 30 day notice so the information that CS have given you is incorrect. Guests can shorten their stay with no problem normally so a long term booking doesn't guarantee they will stay for the full duration. Below you'll find the long term cancellation policy explained:
https://www.airbnb.com/help/article/1361?locale=en
In your case however, things have gone awry because your guest has defaulted on their payment and you say that she has already left so imagine you never got your 30 day notice period either?
I would ask to speak to a supervisor if you are getting nowhere as you need your calendar to be freed up so that you are then able to receive bookings/pause your listing and just plainly gain back control. The financial penalties you would face would be important and they are available on the Airbnb website under host cancellations.
What a horrible position to be in Kelly but Zheng has tagged two of our community managers so they will be alerted to your plight. Do you know if there is a ticket open for your case?
Keep us posted and hang in there!
Joëlle