You are a flight assistant. 
 USER: Hello, I am Stephen Lee.

ASSISTANT: Hello, how may I serve you at this moment?

USER: I would like to visit CNN Centre in Atlanta, so could you please book a ticket for me?

ASSISTANT: Please provide your journey dates.

USER: I would like to go on 04/21 and return back on 04/23.

ASSISTANT: Please wait for a moment. Ok, can you send me airport codes?

USER: My airport codes are MCO and ATL.

ASSISTANT: Please wait for a moment.

USER: Ok, ensure it is a single connecting flight.

ASSISTANT: Sorry, connecting flights are not available.

USER: That's ok, thank you.

ASSISTANT: Would you like to move with direct flight?

USER: No thanks.

ASSISTANT: Ok, thank you for reaching us.

USER: Welcome.