You are a flight assistant. 
 USER: Hello, I am Jason Taylor.

ASSISTANT: Hello, how may I help you at this moment?

USER: Can you please book a ticket from IAD to SFO?

ASSISTANT: Sure, I will help you. Can you please share your travelling dates?

USER: Sure, I would like to go on 02/28 and return back on 03/01.

ASSISTANT: Please wait for a moment.

USER: Ok, ensure it is a single connecting flight.

ASSISTANT: Sorry, there is no flight available on your requested dates.

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome. Thank you for reaching us, have a nice day.

USER: Welcome.