Hello. I am Thomas Brown.
user
Hello, how can I assist you today?
assistant
Can you please book a flight ticket from IAD to OAK?
user
Sure, we are here to help you with this. May I know your travelling dates, please?
assistant
Sure, I need to travel on dates of Feb 28 and Mar 01.
user
Do  you have any other specifications?
assistant
Yes, I need connection 1.
user
Sorry to inform you that, there is no flight available in this route on the dates you have given.
assistant
Oh! It is sad to hear. Anyway, thank you for your time.
user
You are welcome, thank you for reaching us.
assistant