Hi Hannah - I would check the Event Queue on your Notification Server and make sure that NSEs are not backed up. (C:\ProgramData\Symantec\SMP\EventQueue\EvtQueue). You can go to Resource Manager for that computer in the console and then View > Inventory, navigate to Data Classes > Software Management > Patch Management > both the data classes in that folder, and then the Status tab to see the dates to see if they are updating (comes from the Windows System Assessment Scans).
I would also set the year in Release Date From on your compliance by computer report back to 2000 (oldest bulletin is 11/2021 in our feed) and see if any older updates are missing.
If either of those doesn't help, if you open a support case we would be glad to help troubleshoot further.
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