You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: I am Janet Johnson want to change my reservation due to heavy snow storm. Can you help me with it?

ASSISTANT: Sure, please wait a moment.

USER: Ok.

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

USER: Thank you for your help.

ASSISTANT: Thanks for choosing us.