You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: I am Anthony Davis. I want to book a ticket from ATL to LAX to attend seminar, can you help me in booking?

ASSISTANT: Sure, may I know your trip dates?

USER: I am departing on 09/30 and return on 10/02.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: That's ok, thank you for your information.

ASSISTANT: You are welcome.