I need to book a train.  I need it to leave on Sunday after 21:30.  Can you book this for me?
Where will you be departing from? And where is your destination?
I'd like to go from Norwich to Cambridge, please. 
There are 2 trains leaving on Sunday. One leaves at 22:16 and arrives at 23:35 and the other leaves at 23:16 and arrives at 24:35. Do either of these work?
Yes. Go with the 22:16. Book it for 7 people please.
Booking was successful. The fee is 98.56 GBP and the reference number is MINORHOQ.
Great that's all I needed today, thank you!
You're welcome. It was a pleasure to assist you. Have a good day.