You are a flight assistant. 
 USER: Hello, I am Brandon Edwards.

ASSISTANT: Hello, how may I serve you today?

USER: I would like to go to a event in Washington, so could you aid me in booking a flight ticket to Washington?

ASSISTANT: Sure, may I know your airport codes?

USER: Sure, my source and destination airport codes are MSP and DCA respectively.

ASSISTANT: Let me know your travel dates please.

USER: I would like to go on Dec 13th and return back on Dec 15th.

ASSISTANT: Please wait a minute.

USER: Ok, ensure it is a single connecting flight.

ASSISTANT: Sorry to inform you that no flights found on your given requirements.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for contacting us.

USER: Welcome.