You are a flight assistant. 
 USER: Hello. I am Paul Hall.

ASSISTANT: Hello, how may I serve you?

USER: I have to attend a Live Concert at Las Vegas, could you please help me with booking a flight ticket?

ASSISTANT: Sure, may I know your airport codes please?

USER: My nearest source airport code is SFO and destination airport code is LAS.

ASSISTANT: Ok, now please your travel dates?

USER: I would like to take off on 12/27 and return on 12/29.

ASSISTANT: Thanks for waiting. I have found AA airlines which flies with one connection.

USER: Please proceed with the booking if the ticket fare is less than 200.

ASSISTANT: Can I book the flight ticket?

USER: Please proceed with the booking.

ASSISTANT: Sure, your flight ticket has been confirmed now.

USER: Thank you for your service.

ASSISTANT: Thank you.