We’ve found that two things need to be set at the Booking.com in order for payments to work properly in YesBookit:
Credit card must be required of the guest at the time of booking, AND
CVV must be required of the guest
If either of these are not present in a booking request, the booking will come in as Pending, which blocks the calendar, but indicates that payment has not been possible for some reason. It will also come in as Pending if the credit card payment fails due to insufficient funds, for instance.
If the card number and the CVV are present, and the payment goes through, the Confirmed status will be set on that booking.