You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you today?

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

ASSISTANT: Sure, let me know your trip dates?

USER: I planned my trip on the dates Nov 21 and Nov 23.

ASSISTANT: Do you have any connection limit?

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

ASSISTANT: Is there any other specifications?

USER: Yes, I want to take off during afternoon time.

ASSISTANT: May I know your good name?

USER: Sure, myself David Carter.

ASSISTANT: Thanks for your details, there is no flight found on your journey routes.

USER: That's ok, not an issue. Thank you for your help.

ASSISTANT: Thank you for opting us.