You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I want to book a ticket from ORD to JFK. Could you book a ticket?

ASSISTANT: Sure, May I know the travelling dates?

USER: My travelling dates are from Jan, 22 to Jan, 24.

ASSISTANT: Do you have any connection limits?

USER: I would be comfortable with single stop over.

ASSISTANT: Is there any other requirement?

USER: I prefer business class.

ASSISTANT: May I know your name?

USER: David Walker.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, no flights found with your preferable dates.

USER: Thank you.

ASSISTANT: Thank you for opting us.