You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: Can you aid me to book my ticket from DTW to ORD?

ASSISTANT: Sure, will you mention your travelling dates please?

USER: My trip dates are Apr 15 and Apr 17 respectively.

ASSISTANT: Do you have any preferences about flight connections?

USER: I prefer for single connecting flight.

ASSISTANT: Do you have any preferences about class?

USER: No class preferences.

ASSISTANT: Please mention your name.

USER: Stephen Carter here. My depart should be in the evening.

ASSISTANT: The American airlines providing an economy class with price 200 and the connections 1. The Depart time is 20:00 hours.

USER: Please proceed for booking.

ASSISTANT: Your ticket is booked. The flight number is 1020.

USER: Thank you for the help.

ASSISTANT: Welcome, have a great day.