You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am James Roberts.

ASSISTANT: How may I aid you?

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

ASSISTANT: Sure, can you please let me know your airborne and recur travel dates that you have planned for your journey?

USER: Sure, I need to travel on dates of 08/12 and 08/14.

ASSISTANT: Thank for your information, I am unable to find a flight on your dates to book the flight ticket.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Next time we can serve you better and thank you for reaching our agency.

USER: Most welcome.