You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, we are glad to serve you.

USER: Due to sudden change in weather conditions, I need to change my existing reservation.

ASSISTANT: Sure, can I have your name to proceed further?

USER: My name is Kevin Mitchell.

ASSISTANT: ok, please wait for a while, let me check with reservation and let you know. Thanks for waiting, sorry, unfortunately no reservation found with provided name.

USER: Ok, Thanks for your information.

ASSISTANT: Pleasure to serve you, thanks for your interest.

USER: Thank you.