generate response: I'm going to Cambridge, leaving after 13:00. I'll need to book for 7 people. Can I get a reference number too please?. Intent: book_train. Slots: train-bookpeople=7, train-departure=broxbourne, train-destination=cambridge, train-leaveat=13:00
Response: I booked you with TR7015 your reference number is K1AY8EKU .