You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am planning to book a flight ticket to OAK from DFW, can you please help me out?

ASSISTANT: Sure, may I know the trip dates?

USER: Sure, my trip dates are Mar 24 and Mar 26.

ASSISTANT: Do you have any connection limit?

USER: I am looking for a flight with 1 connection.

ASSISTANT: Is there any other requirements?

USER: I prefer business class.

ASSISTANT: May I know your name?

USER: My name is Donna Lewis.

ASSISTANT: Please wait a moment.

USER: Ok, take your time.

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

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

ASSISTANT: Thank you for availing us.