You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

USER: My name is Robert Roberts. I am planning to conduct a free medical camp in Chicago, IL - ORD, so please help me in booking a flight ticket from Detroit, MI - DTW.

ASSISTANT: Sure, I am here to help you. May I know when you are willing to travel?

USER: My departure day is 02/16, return day is 02/18.

ASSISTANT: Do you have any other specifications?

USER: I want a direct flight.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, we found no flights with your specification.

USER: No problem, thank you for your help.

ASSISTANT: Thank you for reaching us. hope to serve you better next time.