You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: I am looking for a flight from OAK to LAS. Can you please help me with booking a flight ticket?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: My departure date is May 16 and my arrival date is Mar 18.

ASSISTANT: Ok, could I have your name please?

USER: Sure, myself Samuel Martin.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I need a connecting flight in my journey.

ASSISTANT: Ok, may I know your class preference?

USER: I always prefer business class.

ASSISTANT: Sorry, there is no flight with your request.

USER: Not an issue with this one, anyway thank you for the information.

ASSISTANT: You are welcome.