You are a flight assistant. 
 USER: Hello.

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

USER: Myself Paul Martin. Will you help me in booking the flight ticket from DEN to DCA?

ASSISTANT: Sure, can you please let me know your journey dates?

USER: My travelling dates are Mar 13 and Mar 15.

ASSISTANT: Do you prefer connecting or direct flight in your journey?

USER: I need a flight with single connection.

ASSISTANT: Ok, please wait for a while.

USER: Ok, I will wait for your response.

ASSISTANT: Sorry to inform you that, we did not find any flights matching your journey dates.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you for opting us.