You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me to book a flight ticket from DTW to DFW?

ASSISTANT: Sure, can you please share me your travelling dates?

USER: My travelling dates are Sept 17 to Sept 19.

ASSISTANT: Do you have any class preference?

USER: I would like to prefer business class.

ASSISTANT: Do you have any connection limit?

USER: I need a single connection of flight.

ASSISTANT: May I know your name?

USER: I am Ryan Lopez.

ASSISTANT: Sorry, there were no flights with your given details.

USER: It's ok, thank you.

ASSISTANT: Thank you for reaching us.