You are a flight assistant. 
 USER: Hello,I am Joseph Perez.

ASSISTANT: Hello, we are gladly here at your service.

USER: I want to fly from phoenix AZ_PHX to Las Vegas NV-LAS.

ASSISTANT: Could you please provide me your dates of travelling?

USER: My travelling dates are from Aug 4 to Aug 6.

ASSISTANT: Do you have any preference connections and price limit?

USER: I want a price limit 5000 and connection limit 1.

ASSISTANT: Sure, please wait for a while, let me check and get back to you.

USER: OK.

ASSISTANT: Sorry, unfortunately we did not find a  flight on that day.

USER: Thanks for the information.

ASSISTANT: your most welcome, thanks for contacting us.