@AusIndo0:
Check your booking requirements. (admin--> booking). Do you have any settings that you have changed recently like requiring additional information? If you have any requirments set other than the Airbnb recommended settings then your listing will only show for people who are logged in and meet the requirments you set. If someone is not logged in the listing will not show at all.
If it has been a while since you looked over every aspect of the listing, then you might go through everything as Airbnb has made several changes in the last couple of months that you may need to adjust.