You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I respond to your request?

USER: I am Jason Clark. Please help me to book an economy class ticket from Washington to visit Olympic National Park.

ASSISTANT: Sure, I am here to help you. Please share your travel dates.

USER: My plan to start on Nov 25th and my return date will be on Nov 27th.

ASSISTANT: Can you please tell airport codes?

USER: My airport codes are from DCA and IAD.

ASSISTANT: Do you have any class preference?

USER: I am comfortable with any class.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: We have a direct flight from Delta airline and the price is 200. Shall I proceed with the booking?

USER: That's fine, you can book the ticket.

ASSISTANT: Your ticket has been booked in economy class and the flight number is 1004.

USER: Thank you for being my helping hand in booking.

ASSISTANT: Thank you for opting us.