You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I would like to meet my family friend on his birthday, so I would like visit Washington.

ASSISTANT: Sure, can you please provide airport codes?

USER: The source and destination airport codes are PHL and IAD.

ASSISTANT: Can you please provide your travel dates?

USER: The dates are 02/14 and 02/16.

ASSISTANT: Please wait a moment, I will inform you.

USER: OK.

ASSISTANT: Sorry, there is no flights found as per your requested dates. May I know your name for documentation process?

USER: That's fine. My name is Gary Campbell.

ASSISTANT: Thank you for your information.

USER: Thank you for your response.