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The BookingCode attribute in ExcursionRate element is used as unique identifier of an offer starting Hotel Excursion Availability response and till the time the booking is confirmed. The BookingCode is valid for limited time (normally 15 minutes); if the reservation was not confirmed (or at least initiated) during this time limit, then new search should be performed again.

As the unique offer identifier, BookingCode should also be used in Price Breakdown and Hotel Charges requestsExcursion Charges request.

BookingCode may change between Availability search and Reservation Initiate response (it depends on supplier specific). In Reservation Confirm Confirmation request, the BookingCode must be taken from the Reservation Initiate response.

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Since an excursion booked, the BookingCode does not play role for the reservation any more. The ExcursionReservationIDs should be used for the booking cancellation.

11.1.3. TRANSACTIONIDENTIFIER

Excursion Reservation and Cancellation should always be done in two steps: 1) Initiation (request/response) and 2)Confirmation or Ignore (request/response). Both these steps have to be done within one transaction.

The TransactionIdentifier allows to recognize which Confirmation or Ignore request relates to the Initiation response.

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Diagram 11.1.3.1. TransactionIdentifier usage