You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you out?

USER: I have planned for the trip to Chicago, can you please find a flight from DFW to ORD?

ASSISTANT: Sure, I am happy to help you. Please let me know your travelling dates.

USER: I am happy for your response. My planned travel dates are Apr 21 and Apr 23.

ASSISTANT: Do you have any connection limit?

USER: I would like to travel in a single connecting flight.

ASSISTANT: Is there any other specifications for you?

USER: No, I didn't have any other specifications.

ASSISTANT: May I know your good name?

USER: My name is Barbara Carter.

ASSISTANT: We are regret to inform you that, no flights are available on your journey routes.

USER: It's ok, not a problem with that. Thank you for your time.

ASSISTANT: Thank you for choosing us.