You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Can you please help me to search a flight with 0 connection limit?

ASSISTANT: Sure, I am here to help out. Please provide me location airport codes.

USER: The airport codes are from PA-PHL to DC-DCA.

ASSISTANT: May I know your trip dates?

USER: The travel dates are 11/23 to 11/25.

ASSISTANT: May I know your name?

USER: Sure, my name is Melissa Phillips.

ASSISTANT: Sorry for the trouble, here I didn't find any flights in your route.

USER: No problem, I will search another way.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your information.