You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: Please help me to book a business class ticket from Oakland to visit Independence Hall in New York.

ASSISTANT: Sure, we are glad to help you. On which dates would you like me to book the flight?

USER: I need to depart on Dec 18th and my return date will be on Dec 20th.

ASSISTANT: Do you have any lay by in between journey?

USER: I want to fly with the connecting flight for this time.

ASSISTANT: Which is your nearest airport code to return?

USER: My take off airport code is OAK and my destination airport code is LGA.

ASSISTANT: Is there any class preference for you?

USER: I have already mentioned above.

ASSISTANT: Sorry, do you have any other specifications?

USER: I want to return from NY in the afternoon.

ASSISTANT: May I know your good name?

USER: I am Paul Collins.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Thank you for your valuable time, unfortunately no flights available on that route.

USER: No issues, I'll choose any alternative to reach my destination. Thank you for your information.

ASSISTANT: Thank you for opting us.