You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am Alexander Jackson. I want to book a ticket from IAD to DCA. Could you help me in booking?

ASSISTANT: Sure, may I know your planned travel dates?

USER: My travelling dates are from 02/21 to 02/23.

ASSISTANT: Do you need halt in between your journey?

USER: I need a direct flight.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, there are no flights found with your given dates.

USER: That's ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.