Today my NortonAntivirus indicated that Security ! needed attention. I opened NortonAntivirus and it automatically ran LiveUpdate. Now, my LiveUpdate says it is current but the Security Alert is still on (see attached image).
Rebooting did not automatically fix the issue, however, after reboot, then opening NA, then clicking "fix now" (again, in the Security tab) it seemed to re-download the updates and then all was fine.
Are you using Norton Antivirus for Mac? Note that "LiveUpdate sometimes requires a (system) reboot". You may provide some few extra information. E.G., have you entered the Security section? Did you find anything re "Autofix" afterwards?
Maybe your NS for Mac detected something.
In some cases, uninstalling your NA for Mac and reinstalling it later would also do the trick. Read this fix if you have trouble doing that yourself.