You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I assist you?

USER: I want to book a ticket from BOS to AUS to attend seminar, can you help me in booking?

ASSISTANT: Sure, May I know the travelling dates?

USER: I am departing on Dec 21 and return on Dec 23.

ASSISTANT: Do you have any connection limit?

USER: I prefer a connecting flight.

ASSISTANT: Is there any other requirements?

USER: I do not have any other specifications.

ASSISTANT: May I know your name?

USER: My name is Stephen Lee.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for opting us.