You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Gregory Brown. I want to book a ticket from DTW to OAK to attend seminar, can you help me in booking?

ASSISTANT: Sure, may I know your trip dates?

USER: I am departing on Dec 14 and return on Dec 16.

ASSISTANT: Do you have any connection limit?

USER: I need a flight with connection limit 1.

ASSISTANT: May I know your class preference?

USER: I am ok with any class.

ASSISTANT: Do you have any other preferences?

USER: I want to depart in afternoon.

ASSISTANT: There are no flights available.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for reaching us.