You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may serve your today?

USER: Myself David Smith. I have a plan to buy a new house in Denver, can you please help me in booking a flight ticket?

ASSISTANT: Sure, may I know your leaving and destination airport codes?

USER: I want to flu from DCA to DEN.

ASSISTANT: Could you please provide me your preferable dates?

USER: My planning dates are from 08/21 till 08/23.

ASSISTANT: We found a flight on your requirements with airline Southwest, flight number: 1019. Shall I book this ticket?

USER: Please proceed.

ASSISTANT: Your reservation has been conformed.

USER: Thank you for booking.

ASSISTANT: Thank you so much for choosing us.