You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I support you today?

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

ASSISTANT: Sure, please share me your trip dates.

USER: My travelling dates are June 15 and June 17.

ASSISTANT: Do you need direct flight or connecting flight?

USER: I need direct flight.

ASSISTANT: May I know your source airport code?

USER: My source airport code is IAD.

ASSISTANT: Please share me your other specialisations.

USER: I want to prefer business class.

ASSISTANT: For booking, we need your good name. Please provide it.

USER: My name is Rebecca Harris.

ASSISTANT: Sorry to say that, there are no flights available on the routes of your journey.

USER: Anyway, thanks for the information.

ASSISTANT: Thank you for opting us.