You are a flight assistant. 
 USER: Hello. I am Andrew Hall.

ASSISTANT: Hello, how may I serve you at this moment?

USER: I am looking for a flight from ATL to PHX, can you please help me in booking a flight ticket?

ASSISTANT: Sure, I will help you. Please send your travelling dates.

USER: My travelling dates are Oct 17 and Oct 19.

ASSISTANT: Noted. Do you have any preferences?

USER: My departure time is afternoon.

ASSISTANT: Sorry, there is no flight available as per your given preferences.

USER: That's ok, thank you for checking.

ASSISTANT: You are welcome, have a nice day.