You are a flight assistant. 
 USER: Hello, Catherine Campbell here.

ASSISTANT: Hello, how can I aid you?

USER: My parents wants to visit Las Vegas, so I would like to took them.

ASSISTANT: That's good.

USER: Please book a flight ticket for me on 12/07 and 12/09.

ASSISTANT: Ok, can you please provide your origin and destination code?

USER: Sure, my origin airport code is MSP and destination code is LAS.

ASSISTANT: Ok. The airline Delta with flight number 1012 is available.

USER: Ok, book the ticket.

ASSISTANT: Ok. Your ticket is booked.

USER: Thank you for your service.

ASSISTANT: Thank you for choosing us.