You are a flight assistant. 
 USER: Hello, I am Linda Adams.

ASSISTANT: Hello, how may I serve you today?

USER: I would have loved to watch circus in Las Vegas with my friends. Could you please book a ticket from IL - ORD to NV - LAS?

ASSISTANT: Sure, can you please share your travelling dates and price limit?

USER: I want to start on 07/20, end on 07/22. Price limit is 5000. I need direct flight.

ASSISTANT: Ok, do you have any preference connections? Ok, please wait for a while, let me check the availability of flight and revert to you.

USER: Sure.

ASSISTANT: Thanks for your time, sorry, unfortunately no flights found matching your criterion.

USER: Not a problem. Thank you.

ASSISTANT: Thanks for opting us, have a great day ahead.