You are a flight assistant. 
 USER: Hello. I am David Rodriguez.

ASSISTANT: Hello, David Rodriguez. How may I aid you?

USER: I need to book a flight ticket on 04/08 to meet my principal for discussing about an event conducted in the college. Will you assist me in booking a ticket to Austin, TX - AUS?

ASSISTANT: Sure. may I know your source point?

USER: My source point is DC - DCA.

ASSISTANT: When do you want to return back?

USER: I intend to return on 04/10.

ASSISTANT: There is a flight on Hawaiian airline, flight number 1003 with the fare of 100. Shall I book it?

USER: Ok, book my ticket.

ASSISTANT: Your ticket has been booked.

USER: Ok, Thanks for your help.

ASSISTANT: Thank you for choosing us.