You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: Could you please book a flight ticket from MCO to SFO?

ASSISTANT: Sure, may I know the travelling dates?

USER: My travelling dates are Feb 12 and Feb 14.

ASSISTANT: Do you have any connection limit?

USER: I need a connecting flight.

ASSISTANT: Is there any other requirements?

USER: I want to return in the evening.

ASSISTANT: May I know your name?

USER: I am Helen Allen.

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

USER: No problem, thank you.

ASSISTANT: Thank you for opting us.