You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I render you today?

USER: I would like to book a flight to Chicago to attend a meeting, can you help me to book a flight ticket with the direct flight?

ASSISTANT: Sure, can you please mention travelling dates?

USER: I intend to depart on Nov 15th and my return date will be on Nov 17th.

ASSISTANT: Could you let me know your airport codes.

USER: My source and destination airport codes are PHL and ORD.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: May I know your name?

USER: I am Jonathan Lewis.

ASSISTANT: We found a direct flight with a Spirit airline, flight number:1001. Can I reserve it?

USER: That's fine, you can proceed with the booking.

ASSISTANT: Your flight ticket has been reserved.

USER: Thank you for your help in booking.

ASSISTANT: Thank you for opting us.