Syncing with TripAdvisor involves 2 parts. First is to import bookings from TripAdvisor to Uplisting and second is to export unavailabilities from Uplisting to TripAdvisor.
Part 1. Importing bookings from TripAdvisor to Uplisting
The following instructions are from TripAdvisor and can be found on their help forum here.
1.1 On TripAdvisor
Sign into your TripAdvisor account. You can also sign into HouseTrip, Niumba, HolidayLettings or FlipKey.
Select Calendar on the left-hand side.
Select 'Manage calendars, then 'Export this calendar'.
Copy the URL.
1.2 On Uplisting
Select the listing on Uplisting you wish to sync with the TripAdvisor listing above.
Select the 'Connect' button on the TripAdvisor row.
Paste the iCalendar link copied from TripAdvisor.
Click 'Next sync availabilities' button to export your unavailabilities to TripAdvisor (instructions below).
2. Exporting unavailabilities from Uplisting to TripAdvisor
2.1 On Uplisting
Copy the 'sync availabilities' iCalendar link provided on Uplisting
Select 'Next: Import bookings'. Uplisting will now import any existing bookings and will sync every 5 minutes and import any new bookings
2.2 On TripAdvisor
Go to your TripAdvisor account
Select the correct property.
Select Calendar and Import Calendar.
Paste the calendar URL you copied from Uplisting.
Give the calendar a name.
TripAdvisor will now import any unavailabilities and mark the TripAdvisor calendar as unavailable on those dates. TripAdvisor will continue to sync intermittently.