You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I am Anthony Clark. I am planning to book a ticket to attend a meeting at BOS. Can you please help me out to book a ticket from LAS?

ASSISTANT: Sure, may I know your travel dates?

USER: I am planning to travel on Nov 16 and return back on Nov 18.

ASSISTANT: Do you prefer economy or business class?

USER: I am ok with any class.

ASSISTANT: Sorry, there is no flight on your details.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you.