You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how best can I assist you?

USER: I am planning to meet my brother at Las Vegas, will you help me in booking the flight in business class from HOU to LAS?

ASSISTANT: Sure, when do you want to start and return on?

USER: My preferable journey dates are Nov 19 and Nov 21.

ASSISTANT: Do you need  a connecting flight?

USER: I need a flight with single connection.

ASSISTANT: Do you have any other specifications?

USER: I would like to return in evening time.

ASSISTANT: Can I know your good name?

USER: Myself Patrick Jackson.

ASSISTANT: Thank you for your details, we found a direct flight 1009 in class economy which is in United airline. Shall I proceed?

USER: I have already mentioned that I need a flight in  business class, can you please help with that?

ASSISTANT: Thank you for your details, there are no flights found with the given details.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you.