You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to visit Denver on 03/20 to 03/22.Can you please help me out?

ASSISTANT: Sure, provide your airport codes please.

USER: The airport codes are from IL-ORD to CO-DEN.

ASSISTANT: May I know your name?

USER: Sure, my name is Anna Phillips.

ASSISTANT: Ok, there is a flight for you with flight number 1020. Shall I proceed?

USER: Ok, proceed with my booking.

ASSISTANT: Ok, your ticket has been done with the airline Frontier.

USER: Thank you for your service.

ASSISTANT: Thank you.