Booking have changed the system for Synchonising the Calendar.
IT IS TYPICAL OF BOOKING TO MAKE A CHANGE WITHOUT PRIOR NOTICE TO PARTNERS.
With the changes Booking made our previous calendar synchronisation was nulled and as a consequence 2 double booking came in. Only then did we realise of the change. Later today we received a message from Booking in our extranet inbox, with a lot of fanfare, advising us of the change!!
Please, Please don't make such drastic changes without notice.