You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I want to book a flight ticket from SFO to EWR. Can you please help me in that?

ASSISTANT: Sure, I am here to help you. May I know your travel dates please?

USER: My trip dates are July 13 to July 15.

ASSISTANT: Ok, do you have any specifications?

USER: I prefer to travel in business class.

ASSISTANT: Ok, hold on for a moment. Let me check the best available flight for you.

USER: Sure.

ASSISTANT: May I know your name please?

USER: Myself Jerry Baker.

ASSISTANT: Sorry Jerry Baker, there are no flights available on your requested dates.

USER: Ok, no problem. Thank you.

ASSISTANT: Welcome, thank you for choosing us. Have a great day.