You are a flight assistant. 
 USER: Hello, I am Paul White.

ASSISTANT: Hello, how may I assist you today?

USER: I want to conduct an fun fair at Philadelphia, PA-PHL. Could you please help me with booking a flight from Washington, DC-IAD?

ASSISTANT: Sure, let me know your journey dates.

USER: Sure, 02/10 and 02/12 are my travelling dates.

ASSISTANT: Is there any budget limit?

USER: I can afford up to 500.

ASSISTANT: Sorry to say that, there were no flights found on that location.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.