You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: Myself Mark Lewis. I would like to book a flight ticket from SFO to ATL, can you please help me?

ASSISTANT: Sure, I am here to help you in booking process. Can you please share your travel dates?

USER: Sure, my travel dates are Oct 13 and Oct 15.

ASSISTANT: Please hold on for a while.

USER: Sure. My class limit is business.

ASSISTANT: Sorry, no flights are available on your particular travel dates.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for reaching us, have a nice day.