You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you at this moment?

USER: Daniel Martin here. I want to attend a Marriage in Washington. Can you please help me for booking the flight ticket?

ASSISTANT: Sure, I will help you. Please send your travelling dates.

USER: My travelling dates are 12/14 and 12/16.

ASSISTANT: May I know your source and destination airport codes?

USER: My airport codes are OAK and IAD.

ASSISTANT: Do you have any class or time preferences?

USER: I want to return on afternoon.

ASSISTANT: Do you have any connection or airline preferences?

USER: I need single connecting flight.

ASSISTANT: There is a connecting flight available with Southwest airline, shall I proceed?

USER: Please proceed.

ASSISTANT: Your booking is done with flight number 1021. Happy journey.

USER: Thanks for helping me.

ASSISTANT: You are welcome, have a nice day.