You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know how best I can help you today?

USER: I am Charles Wright. I am planning to book a ticket from DCA to LAS. Can you please help me out to book a ticket for me?

ASSISTANT: May I know on which dates you are willing to travel?

USER: I would like to travel on Jan 13 and return back on Jan 15.

ASSISTANT: There is a direct flight in Delta airlines with the fare 100.

USER: Yes, please proceed the booking.

ASSISTANT: Your booking is done.

USER: Thank you for your service.

ASSISTANT: Thank you.