You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: Can you help me with booking ticket from DFW to OAK?

ASSISTANT: May I know on which dates you are willing to travel?

USER: OK, my trip dates are from Sept 14 to 16.

ASSISTANT: May I know your departure time and arrival time?

USER: Sure, I would like to departure in the afternoon.

ASSISTANT: Do you require any connections in your journey?

USER: Yes, I need a connecting flight.

ASSISTANT: Do you have any other requirements?

USER: I need a flight in business class.

ASSISTANT: May I know your name?

USER: Sure, I am Laura Young.

ASSISTANT: Sorry to inform you that unfortunately there is no flights available by the given details.

USER: It's ok, thanks for your information.

ASSISTANT: Thank you.