You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: Myself Robert Davis. My college is going to celebrate the Science Exhibition at Denver, DEN.

ASSISTANT: Ok.

USER: Please book a ticket on 04/10 under the price limit of 5000.

ASSISTANT: Sure, may I know your origin airport code?

USER: Las Vegas, LAS is my boarding point.

ASSISTANT: On which date would you like to return?

USER: I would like to return on 04/12.

ASSISTANT: We found a flight on your details with airline Frontier, flight number: 1004.

USER: Ok.

ASSISTANT: Shall I book this ticket?

USER: Confirm it.

ASSISTANT: Your ticket has been booked.

USER: Thank you for guiding me.

ASSISTANT: Thank you so much for choosing us.