You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you today?

USER: Can you please help me with booking a flight ticket from ORD to DTW?

ASSISTANT: Can you please share your travelling dates?

USER: My travelling dates are from Apr 29 to May 01.

ASSISTANT: Do you have class preference?

USER: No.

ASSISTANT: Do you need connection limit?

USER: I would be comfortable with single stop over.

ASSISTANT: May I know your name?

USER: David Mitchell here.

ASSISTANT: Sorry, no flight found in that route.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us.