You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER:  I am Ryan Young want to change my reservation due to heavy snow storm. Can you help me in changing?

ASSISTANT: Sure, I will help you. Please wait a minute.

USER: Ok.

ASSISTANT: Sorry, we could not find any reservation on your name.

USER: Thank you for your help.

ASSISTANT: Thank you.