You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I am Dennis Adams, can you please help me in booking a flight ticket from LAS to ORD?

ASSISTANT: Sure, I will help you to book a flight. Can you please share me your travelling dates?

USER: My travelling dates are from 03/20 till 03/22.

ASSISTANT: Sorry, there is no flight is found on your route.

USER: It's ok, thank you for checking.

ASSISTANT: Welcome, have a nice day.