You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Joseph Young.

ASSISTANT: How may I help you?

USER: I am planning to attend convocation meeting at Seattle, can you please help me with booking a flight ticket?

ASSISTANT: Sure, please provide your airport codes.

USER: My source airport code is AUS and the destination airport code is SEA.

ASSISTANT: May I know your travelling dates please?

USER: Sure, I would like to take off on 05/13 and return back on 05/15.

ASSISTANT: Please wait a moment.

USER: OK, but please make sure that the price limit is 200.

ASSISTANT: I found a flight for you in Frontier airlines with price 200. Can I proceed?

USER: Yes, please proceed with the booking.

ASSISTANT: Ok, your booking is confirmed with flight number 1014.

USER: Thank you for your help.