You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Andrew Lee. Please book a flight ticket to Phoenix, AZ from Washington, DCA.

ASSISTANT: May I know your desired travel dates please?

USER: I want to travel on Aug 16 and return back on Aug 18.

ASSISTANT: Please share your destination airport code.

USER: Destination airport code is PHX.

ASSISTANT: There is a flight with connection limit 1 and fare 200, shall I proceed for booking?

USER: Yes, proceed.

ASSISTANT: Your ticket is booked, flight number 1000.

USER: Thank you for your service.

ASSISTANT: Thank you for opting us.