Please note that if you want to sell bed in a dorm your listing needs special configuration. The number of guests should be set up to 1.
Why it's necessary? Because if you set up a dorm with 5 guest occupancy and you have only 2 beds free, the system will be sending the information to Airbnb about 2 FREE rooms, but the channel will see it as two free rooms for 5 guests and not 2.
So if you need to set up the maximum occupancy 1. In practice if a guest wants to book 5 beds, he needs to make 5 separate bookings for a dorm.
We recommend this solution if you want to sell dorms on Airbnb and avoid overbookings.
Go to Menu / Listings. Choose your listing and in Listing details tab go down and seach Number of guests option. Put 1 there.