You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: My name is Gregory Lee, I want to book a flight in morning from Las Vegas to spend my holidays. Can you help me with booking?

ASSISTANT: Sure, let me know your travelling dates?

USER: I will fly on Dec 30 and return on Jan 01.

ASSISTANT: May I know your destination airport code?

USER: My destination point is Denver.

ASSISTANT: Is there any class preference?

USER: I need a business class.

ASSISTANT: Do you prefer direct flight or connecting flight?

USER: I prefer connecting flight.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for your time, there is no found on your requested journey locations.

USER: Thank you for the information.

ASSISTANT: Thank you for approaching us.