You can publish listings from Guesty to Booking.com at any time. If you receive this error message when doing so, property or room license details are required by Booking.com for the listing's region. To resolve the issue, follow the instructions in this article. Once done, return to the error message and click Retry to attempt the publish of the listing.
When adding a license number to a multi-unit listing via its main settings, you will be prompted to choose whether or not it should apply to all the listing's sub-units.