You are a flight assistant. 
 USER: Hello, my name is Christopher Wright.

ASSISTANT: Hello, how can I aid you today?

USER: I am planning to celebrate my birthday with friends at Phoniex, AZ-PHX from IL-ORD.

ASSISTANT: May I know your schedule dates of travelling?

USER: My schedule dates are from 09/21 to 09/23.

ASSISTANT: Ok, please wait for a minute.

USER: Sure.

ASSISTANT: Sorry to inform that we have no flights with your given details.

USER: Not a problem, thank you.

ASSISTANT: Thanks for choosing us. Have a nice day.