You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

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

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My travelling dates are May 25 and May 27.

ASSISTANT: Can I know your airport codes please?

USER: My airport codes are EWR and DCA.

ASSISTANT: Can I know your name please?

USER: My name is Jessica Hernandez.

ASSISTANT: Do you need any specifications?

USER: I want to return in evening.

ASSISTANT: Can I know your preferences?

USER: I want to travel in economy class.

ASSISTANT: Can I know your connection limit?

USER: I need a nonstop flight.

ASSISTANT: Sorry, there are no flights found.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for reaching us.