How can I detect UNENROLL in a benefits enrollment?

Good afternoon, Community.

I have a question and would appreciate your guidance.
I'm managing event benefits without restrictions, allowing users to unenroll from a benefit at any time after applying. My goal is to allow users to unsubscribe or cancel a benefits plan. I haven't implemented a cancellation option because users have multiple options and can unsubscribe from only one while remaining subscribed to the others.

How can I identify or generate an alert to notify the administrator when a user unenrolls from an option or plan?

Thank you for your help and support.

Regards,

Orlando