You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am planning to visit Institute of Chicago with my students, can you help me with booking?

ASSISTANT: Sure, may I know your source and destination airport codes?

USER: My airport codes are DFW to ORD.

ASSISTANT: Do you want connecting flight or direct flight?

USER: I am comfortable with any connection.

ASSISTANT: Let me know your travelling dates.

USER: I will fly on Oct 25 and recur on Oct 27.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: May I know your name please?

USER: I am William Walker.

ASSISTANT: We found a Delta airline, flight number: 1007, price: 100 with one connection.

USER: Please proceed with booking.

ASSISTANT: Your flight ticket has been confirmed.

USER: Thank you for helping me.

ASSISTANT: Thank you for choosing us.