i need a train on friday .
user
okay . what day would you like to travel ? what time would you like to leave ? where are you departing from and what is the destination please ?
assistant
i am going to cambridge coming from london kings cross . i will be leaving on friday after 16:30 .
user
ok , the earliest departure i have is 17:17 . would you like to book it ?
assistant
how much is a ticket ?
user
i do not have that information available .
assistant
can i at least get the train id ?