You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you for the day?

USER: Can you please help me with booking a flight ticket from PHL to DCA?

ASSISTANT: Can you please share your travelling dates?

USER: My travelling dates are from Jun 23-25.

ASSISTANT: Do you have class preference?

USER: No, I am comfortable with any class.

ASSISTANT: Do you need connection limit?

USER: I need a connecting flight.

ASSISTANT: Would you like to prefer airline?

USER: I prefer normal cost airline.

ASSISTANT: Is there any other specifications?

USER: I need to return in afternoon.

ASSISTANT: May I know your name please?

USER: Sure, William Thompson here.

ASSISTANT: Sorry, no flight found in that route.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.