You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Benjamin Walker.

ASSISTANT: How can I assist you now?

USER: Can you please book me a plane ticket from PHX to ORD?

ASSISTANT: Sure, I will help you with that. Can I have your travel dates please?

USER: Sure, my planned travelling dates are from 07/17 to 07/19.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Sorry Walker, no flight is available to you on your dates. Thank you for choosing us, have a great day.

USER: It's ok, thank you.

ASSISTANT: My pleasure.