Task-oriented dialogue about: train

I need to leave Cambridge on Sunday by train.
The first train to leave Cambridge departs at 5:00, and goes to London kings cross.
That will be fine I guess. It will arrive by 19:15, I'm sure?
TR2045 will arrive closer to that time, it arrives at 18:58. Would you like tickets for that one instead?
Yes, let's go ahead and book that.
My apologies, I believe there was an error in the database lookup. TR2045 is not available but TR3353 arrives at 17:51 on Sunday. Shall we book that instead?
Yes, please give me travel time and departure time, please.
Certainly. The departure time is 17:00 and the travel time is 51 minutes. I have booked your ticket. The reference number is BJJ3GXMX. Can I help with anything else?
No, that's all I need, thank you.
Thank you for using our system!
Thanks for your help bye!
You are welcome. Goodbye.