Find My Mac discrepancy between system settings and iCloud.com

Find My Mac is enabled in system settings, but on iCloud.com and all my other devices, it shows Find My Mac off. The Mac is not appearing in the Find My app. I've tried many things but Find My Mac just isn't working.

[Re-Titled by Moderator]

Original Title: Find My Mac is enabled in system settings, but on iCloud.com and all my other devices, it shows Find My Mac off.