You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want to attend a Seminar in Boston. Can you please help me for booking the flight ticket?

ASSISTANT: Do you have any preference?

USER: I want to depart in afternoon.

ASSISTANT: Can I know your airport codes?

USER: My airport codes are PHL and BOS.

ASSISTANT: Is there any connection limit?

USER: I prefer single connecting flight.

ASSISTANT: Let me know your travelling dates.

USER: My travelling dates are June 25 and June 27.

ASSISTANT: Can I know your name?

USER: My name is Shirley Harris.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you.