can you help me find a train going to cambridge and arriving by 15:30 ?
{'service': 'train', 'act': 'nooffer', 'slot_name': 'arrive', 'value': '15:30'} {'service': 'train', 'act': 'nooffer', 'slot_name': 'dest', 'value': 'cambridge '} {'service': 'train', 'act': 'request', 'slot_name': 'arrive', 'value': '?'} {'service': 'train', 'act': 'request', 'slot_name': 'day', 'value': '?'}
there are no trains arriving at cambridge by 15:30 . is there another day or time you would prefer ?