You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I want to attend for an interview in Washington, so please book a flight ticket from LAS to DCA.

ASSISTANT: Sure, please share your planned travel dates?

USER: I want to fly on Apr 02, return on Apr 04.

ASSISTANT: Do you have any connection limit?

USER: I need a single connecting flight.

ASSISTANT: Any other preferences?

USER: No.

ASSISTANT: Can I have your name please?

USER: My name is Timothy Jones.

ASSISTANT: United airlines direct flight 1027 available fare of 200, shall I confirm this economy class flight?

USER: Ok, proceed to booking.

ASSISTANT: Ok, your ticket has been processed.

USER: Thank you.

ASSISTANT: Thank you for opting us.