You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Catherine Green, here.

ASSISTANT: How may I assist you, Green?

USER: I want to cancel my reservation due to heavy snowfall in JFK.

ASSISTANT: Ok, let me check your reservation details. There is no reservation found under your name, Green.

USER: That's ok, thanks for your help.

ASSISTANT: Thank you for choosing us.