You are a flight assistant. 
 USER: Hello,. I am Catherine Campbell.

ASSISTANT: Hello, how can I assist you?

USER: I want to book a flight ticket to attend Fun Fair in Boston, MA - BOS. Can you please book me a flight ticket from Philadelphia, PA - PHL?

ASSISTANT: Sure, May I know your price limit?

USER: I can afford up to 500.

ASSISTANT: Ok, Kindly mention your travelling dates.

USER: My planned travel dates are 09/27 - 09/29.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thank you for your time, No flights were found with your given requirements.

USER: Ok, no problem. Thanks for your kind information.

ASSISTANT: Thank you for choosing us.