You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Is there any help that I can assist you today?

USER: I want to attend a Seminar in New York. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, can I know your travelling dates?

USER: My travelling dates are Feb 22 and Feb 24.

ASSISTANT: Please share your source and destination codes.

USER: My airport codes are DEN and LGA.

ASSISTANT: Is there any class that you require for this journey?

USER: I prefer business class.

ASSISTANT: May I know your name please?

USER: My name is Brian Martin.

ASSISTANT: Any other specifications, please provide it.

USER: I prefer single connecting flight.

ASSISTANT: Sorry, non of the airlines is providing a flight for your journey to book a ticket.

USER: Anyway, thanks for the information.

ASSISTANT: Most welcome and have a nice day.