You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

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

ASSISTANT: Sure, may I know your travelling dates?

USER: My travelling dates are Oct 5 to Oct 7.

ASSISTANT: Can I know your connection limit?

USER: I need a single connection of flight.

ASSISTANT: Can you please help me with your class preference?

USER: I am comfortable with any class.

ASSISTANT: May I know your name?

USER: Frank Martinez here.

ASSISTANT: Sorry, there are no flights available on your travelling dates.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for choosing us.