You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I am looking for a flight from IAD to JFK, can you help me out?

ASSISTANT: Sure, help me with the trip dates?

USER: Sure, my trip dates are from May 27th till May 29th.

ASSISTANT: May I know your name please?

USER: Myself John Mitchell.

ASSISTANT: Do you have any preferences?

USER: I prefer to travel in business class flight.

ASSISTANT: Sorry, no flights were available at this moment.

USER: That's ok, not an issue.  Thank you.

ASSISTANT: Thank you for reaching us.