generate response: Yeah, book the one that leaves at 15:29 please, for 4 people. Give me the reference number too.. Intent: book_train. Slots: train-bookpeople=4, train-day=sunday, train-departure=cambridge, train-destination=bishops stortford, train-leaveat=15:15, after 15:00.
Response: It has been booked for you and your reference number is P56PSPSX .