You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Could you please help me to book a flight ticket from OAK to ORD?

ASSISTANT: Can you share your journey dates?

USER: My travelling dates are Feb 21 and Feb 23.

ASSISTANT: Do you need any connection limit?

USER: I am comfortable with any flight.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: May I know your name?

USER: I am James Mitchell.

ASSISTANT: There are no flights available on your journey dates.

USER: Not a problem, thank you for the information.

ASSISTANT: Thank you for opting us.