Task-oriented dialogue about: train

I'm looking for a train leaving on sunday going to cambridge.
where are you departing from?
I want to depart from London Liverpool Street after 15:00.
There is a train leaving on that date from london liverpool to cambridge at 15:39, arrive at 17:07 with a price of 13.28 pounds. Would you like to book?
No, I will book it myself later. Thanks, that's all I need.
I hope you have a good trip. Thanks calling in today. Goodbye.