You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am planning to visit Austin to meet my friend, can you please help me in booking a flight ticket from DCA to AUS?

ASSISTANT: Sure, can you please help me with your travelling dates?

USER: My travelling dates are Feb 14 and Feb 16.

ASSISTANT: Do you have any connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you have any other preferences?

USER: I want to depart in afternoon.

ASSISTANT: Can I know your name, please?

USER: My name is Stephen Wilson.

ASSISTANT: Sorry, there are no flights available on your request.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for choosing us.