You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you at this moment?

USER: I want to book a flight ticket from DCA to SEA, so please help me in booking a flight ticket.

ASSISTANT: Sure, I am here to help you. Could you please provide your journey dates?

USER: I would like to fly on Mar 10 and return on Mar 12.

ASSISTANT: Do you have any class preference for this trip?

USER: I am comfortable with any class.

ASSISTANT: May I know your connection limit for this journey?

USER: I need a single connection.

ASSISTANT: Do you have any specific depart and arrival timings for this journey?

USER: I would like to return in the morning time.

ASSISTANT: May I know your airline preference?

USER: I am comfortable with any airline.

ASSISTANT: For further proceedings, please provide your name.

USER: I am Raymond King.

ASSISTANT: Raymond King, there are no flight services are available on this route with your preferences.

USER: Not an issue. Thank you.

ASSISTANT: Thank you for opting us.