You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Andrew Davis here.

ASSISTANT: How may I assist you?

USER: I'm planning to visit Austin, can you please help me in booking the ticket from DCA to AUS?

ASSISTANT: May I know your journey dates?

USER: Yes, my planned departure and return travel dates are 12/01 and 12/03.

ASSISTANT: A flight is available by UA airlines, can I proceed with booking?

USER: May I know the ticket fare?

ASSISTANT: The fare is 100.

USER: That's fine for me, you can proceed for booking the ticket.

ASSISTANT: Your booking is done.

USER: Thank you so much for your help in booking the ticket.

ASSISTANT: Thank you for choosing our services.