You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you at this moment?

USER: I want to book a flight ticket from San Francisco to Detroit. Can you help me?

ASSISTANT: Sure, I am here to help you. Can you please provide your journey dates?

USER: Thank you for your positive response. My journey dates are Mar 13 and Mar 15.

ASSISTANT: Do you have any connection limit preference?

USER: Yes, I am looking for a connecting flight.

ASSISTANT: Do you have any other specifications for this trip?

USER: Yes, I prefer evening flight at the time of take off from San Francisco.

ASSISTANT: May I know your name to proceed further?

USER: Please reserve the ticket under the name Mark Moore.

ASSISTANT: Mark Moore, there are no flight services available on this route with your preferences.

USER: No issue, I will go with other agency. Anyway thank you for checking.

ASSISTANT: Thank you for contacting us.