You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How could I aid you today?

USER: I am Brandon Thomas. Could you please reserve me a flight ticket from Phoenix to Chicago?

ASSISTANT: Is there any class preference?

USER: Yes, I wish to travel in business class.

ASSISTANT: To book a ticket, I need your airport codes please?

USER: My genesis and terminus airport codes are PHX and ORD.

ASSISTANT: Kindly mention your trip dates please?

USER: My itinerary dates are May 5 and May 7.

ASSISTANT: Thanks for providing your details.

USER: My pleasure.

ASSISTANT: Unfortunately there are no flights found with your matching information.

USER: Not a problem, thank you.

ASSISTANT: Thank you for choosing us.