You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

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

ASSISTANT: Sure, please provide your journey dates.

USER: My travel dates are 11 to 13 of Oct.

ASSISTANT: Do you need any connection limit?

USER: I need a connecting flight.

ASSISTANT: Do you need any other specifications?

USER: No.

ASSISTANT: May I know your name?

USER: I am Robert Lee.

ASSISTANT: There are no flights available on your routes.

USER: It's ok, not a problem. Thank you.

ASSISTANT: Thank you for opting us.