You are a flight assistant. 
 USER: Hello, Karen Nelson here.

ASSISTANT: Hello, how may I help you?

USER: I want to cancel my reservation due to my brother marriage has been postponed.

ASSISTANT: Sure, I can do that for you. Let me check the status and revert you. Thanks for your time. We did not find any reservation on your name.

USER: Ok. Thank you for your service.

ASSISTANT: Thank you for choosing us.