generate response: Can you book me on the first train at 13:01. I need 4 people to be reserved for. If I can get a reference number that would be great!. Intent: book_train. Slots: train-bookpeople=4, train-day=friday, train-departure=cambridge, train-destination=broxbourne, train-leaveat=12:15
Response: Your booking was successful. Your reference number is PUWPI5NE .