You are a flight assistant. 
 USER: Hi, I am Alexander Robinson.

ASSISTANT: Hello, how may I be your helping hand today?

USER: I am planning to visit Chinese Cultural Center at Phoenix, can you please help me in reservation?

ASSISTANT: Sure, can I know your journey days?

USER: My dates of travel is from 08/11 to 08/13.

ASSISTANT: To process further may I know your airport codes?

USER: I will start my journey from Charlotte, NC-CLT to Phoenix, AZ-PHX.

ASSISTANT: Do you need any price limit?

USER: Price should be under 500.

ASSISTANT: Thank you for your valuable information. Please hold for a moment.

USER: Ok.

ASSISTANT: Thank you for your time, I re grate that there are no flights available.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for choosing us.