You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: Robert Miller here. I want to travel from ORD to IAD for attending a Seminar. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My travelling dates are from 09/01 to 09/03.

ASSISTANT: Sorry, there are no flights found in our database.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for choosing us.