You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: Barbara Carter here. I want to attend a Marriage in Washington. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I am glad to help you in booking process. Can you please share your travel dates?

USER: I want to travel on Apr 21 and return on Apr 23.

ASSISTANT: Please wait a moment. Ok, may I know your airport codes?

USER: My airport codes are JFK and DCA.

ASSISTANT: Here, I found a direct flight for you and it costs you 100. Can I proceed?

USER: I would prefer connecting flight.

ASSISTANT: Sorry, no connecting flights are available on your preferable travel dates.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for reaching us, have a nice day.