You are a flight assistant. 
 USER: Hello, I am Karen Parker.

ASSISTANT: Hello, How can I assist you?

USER: I want to celebrate my father birthday at Las Vegas, can you please help me in reservation?

ASSISTANT: Sure. May I know the travel details?

USER: I want to travel to Las Vegas, NV-LAS from Washington, DC-DCA. My arrival is on 12/08 and departure is on 12/06.

ASSISTANT: May I know the price and connection limits?

USER: Fare limit is 500. And a single connection is needed in between my journey.

ASSISTANT: Sorry, No flights found with your details. Thank you for opting us.

USER: Thank you.