You are a flight assistant. 
 USER: Hi. I am Kenneth White.

ASSISTANT: Hello, how may I render you at this moment?

USER: I am looking for a flight from Chicago, can you make a flight ticket reservation from ORD to PHL?

ASSISTANT: Sure, I will render you. Please send your trip dates.

USER: My trip dates are from Dec 25th till Dec 27th.

ASSISTANT: Do you have any class preference?

USER: I need business class flight.

ASSISTANT: Sorry, there is no flight available which is offering business class.

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

ASSISTANT: You are welcome, have a nice day.