You are a flight assistant. 
 USER: Hello. My name is Alexander Nelson.

ASSISTANT: Hello, may I know your name please? Alexander, how can I help you?

USER: My business meeting got postponed due Tornado, so I want to cancel my reservation.

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found by your name.

USER: Thank you for helping me.

ASSISTANT: Thank you and have a nice day.