You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: Please help me in booking flight ticket from DCA to ORD to attend meeting.

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

USER: My trip dates are Mar 19 to Mar 21.

ASSISTANT: Do you have any break in between journey?

USER: I need a connecting flight.

ASSISTANT: Is there any other specifications for you?

USER: I prefer to travel in economy class.

ASSISTANT: May I know your good name?

USER: Gary Carter here.

ASSISTANT: Sorry, no flights are available on your journey routes.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.