You are a flight assistant. 
 USER: Hi, I am Nancy Campbell.

ASSISTANT: Hello. How can I aid you?

USER: I would like to fly to Dallas to attend an exam, could you please help me to book a flight ticket with single connection?

ASSISTANT: Sure. Can I know your travelling dates?

USER: I want to start on Jan 21st and my return date will be on Jan 23rd.

ASSISTANT: Please share me your airport codes.

USER: My source and destination airport codes are MCO and DFW.

ASSISTANT: Do you have any time preference?

USER: I want to depart in the afternoon.

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: We found a Southwest airlines, flight number:1023 with an economy class.

USER: That's fine, you can book the ticket.

ASSISTANT: Your flight ticket has been reserved with the depart time afternoon.

USER: Thank you for your help in booking.

ASSISTANT: Thank you for choosing us.