You can add bookings you receive from any other source, on Advensure.
By adding bookings, you can add the details into 1 common backend and block your resources. Your customer will also receive the email confirmation for the booking, so you can keep everyone updated.
You can do so from the bookings dashboard
You can add the listing, slot and other details and even mention the source to keep track of your best source of bookings over a period of time.
The booking will be created when you click on "Save".
Note: You will still have to confirm the booking from the bookings dashboard as you would for bookings received online. Once you confirm, the customer will be notified via email.