You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: My son is giving a presentation on international competition, but due to some sudden changes, I want to change my existing reservation.

ASSISTANT: Sure, may I know your name please?

USER: Sure, my name is Elizabeth Perez.

ASSISTANT: May I know your airport codes?

USER: My new airport codes are SEA to AUS.

ASSISTANT: Could you please provide your trip dates?

USER: Sure, I will go on 04/27 and return on 04/29.

ASSISTANT: There is a flight for you with 1016 in Delta airline.

USER: Ok, please proceed.

ASSISTANT: Ok, your ticket has been booked.

USER: Thank you for your service.

ASSISTANT: Thank you for choosing us.