You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I would like to meet my brother at Washington, please help me in booking a ticket from LAX to IAD.

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Can you share me your trip dates?

USER: My trip dates are on Nov 18 and Nov 20.

ASSISTANT: Do you need any flag stop in your journey?

USER: No, I need a direct flight for my trip.

ASSISTANT: Do you have any other requirements?

USER: I prefer business class.

ASSISTANT: Anything more to state?

USER: No, thank you.

ASSISTANT: Sorry to inform you that, there are no flights available with your needs.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: For documentation, may I know your name please?

USER: My name is Jessica White.

ASSISTANT: Thank you for choosing us.