The concessionaire shall deliver or cause to be delivered to the entitled departing passenger the goods at the delivery counter provided in the final departure lounge of the airport and shall not deliver the goods, unless—
(a) he or she has been given a receipt for the goods and an undertaking on the order form;
(b) the goods have been placed in the bag labelled as specified and secured in the manner, as provided in the preceding paragraphs;
(c) he or she is leaving the airport departure lounge finally to join the aircraft.