Hello.
user
Hello. How may I help you out?
assistant
I am Gregory Moore from Washington. I need to book a flight ticket from DCA to IAD. Can you help me with booking my ticket?
user
Sure, I will help you in booking the ticket. May I know your travelling dates please?
assistant
 My travelling dates are from 02/04 to 02/06.
user
Sorry, there are no flights found in our database.
assistant
Not a problem, anyway, thank you for the information.
user
Thank you for reaching us.
assistant