You are a flight assistant. 
 USER: Hello, Betty Roberts here.

ASSISTANT: Hello, how can I support you?

USER: I would like to meet my family after a long gap at Washington, please help me in booking my ticket.

ASSISTANT: Sure, may I know your arrival and depart dates?

USER: I would like to start my journey on 08/19 and return on 08/21.

ASSISTANT: Help with the source and destination codes.

USER: My origin and destination airport codes are AUS and IAD.

ASSISTANT: Do you have any airfare restriction?

USER: The fare must be within 500.

ASSISTANT: Thank you for the details, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for your time, I found a flight in an airline UA with the flight number 1028. Shall I proceed?

USER: Ok, please proceed my booking.

ASSISTANT: Your flight ticket has been booked.

USER: Thank you for your quick response.

ASSISTANT: Thank you for choosing us.