You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Raymond Baker.

ASSISTANT: How can I help you today?

USER: I am planning to attend music concert at LAS, can you please help me with booking a flight ticket from JFK?

ASSISTANT: Sure, can I know your preferable dates?

USER: Sure, I would like to take off on Aug 3 and return on Aug 5.

ASSISTANT: Do you have any specifications?

USER: Yes, I prefer business class.

ASSISTANT: Sorry, no flights are available on your desired route.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.