You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: Please help me in booking flight ticket from DCA to DTW.

ASSISTANT: Sure, can you share me your travelling dates?

USER: My trip dates are July 25 to July 27.

ASSISTANT: Do you have any class preference?

USER: I want to fly in business class.

ASSISTANT: Is there any other specifications?

USER: I need a connecting flight.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: May I know your name please.

USER: Myself Katherine Walker.

ASSISTANT: Sorry, no flights are found on your travelling dates.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.