You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am planning to book a ticket from ORD to LAS, can you please help me out?

ASSISTANT: Sure, may I know your planned travel dates?

USER: I am travelling on these dates Sept 18th and 20th.

ASSISTANT: Do you have any class specification on your journey?

USER: I need a single connected flight. I prefer business class.

ASSISTANT: May I know your name for the booking process?

USER: James Allen here.

ASSISTANT: Do you have any another specifications?

USER: I don't have any other specifications?

ASSISTANT: Unfortunately, no flights available on your requirements.

USER: Ok no problem, thank you for your services.

ASSISTANT: Welcome, thank you for reaching us.