You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I need to travel from ATL and LGA, can you please reserve flight ticket ?

ASSISTANT: Sure, can you share your trip dates?

USER: My travelling dates are Sept,17 and Sept,19.

ASSISTANT: Do you have any preferences?

USER: I prefer economy class with single connecting flight required.

ASSISTANT: May I know your name?

USER: Myself Brian Martinez.

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

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

ASSISTANT: Thank you for reaching us.