You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you now?

USER: Can you help me to book a direct flight from DCA to LAS?

ASSISTANT: Sure, I am oblige to help you with flight ticket booking and may I know your travelling dates?

USER: My travelling dates are 07 and 09 of Sep.

ASSISTANT: For booking the flight ticket, may I know your name please?

USER: I am Robert Baker.

ASSISTANT: Do you have any other specifications for your journey?

USER: I would like to depart in the evening.

ASSISTANT: I have found a flight on your requirements in Hawaiian airlines with a fare of 100, do you want me to proceed with booking?

USER: Please proceed with the booking.

ASSISTANT: Your flight ticket is booked in 1009 flight which will depart at 20:00 PM.

USER: Thanks for helping me.

ASSISTANT: You are welcome and  have a happy journey.