You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What can I do for you?

USER: My name is Mary Young. I want to book a flight on 07/16 and return date 07/18. Can you help me with it?

ASSISTANT: May I know your airport codes please?

USER: Yes, my source airport code is PHX and destination airport code is ATL.

ASSISTANT: Just a moment please.

USER: Sure.

ASSISTANT: I am sorry to say, no flights found on you details.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you for choosing us.