generate response: I've mixed up my locations. I actually need a train that departs from Cambridge and goes to Stevenage.. Intent: find_train. Slots: train-arriveby=dontcare, train-day=wednesday, train-departure=cambridge, train-destination=stevenage, train-leaveat=20:45
Response: I only have two trains that leave from Cambridge Wednesday. The TR9016 departs at 21:21 and the TR6387 departs 23:21.