Defender is eating up resources trying to scan (and failing)


I installed Defender a few weeks ago and its was working fine. Today I logged in to see a scan on 100% (but not finishing) and according to the server process' it seems to be eating up memory.
Now when I go to the Defender Scan page, I click Cancel Scan but it doesn't do anything.
I even tried disabling and re-enabling the plugin but the scan continues from 100% without user interaction.
While the plugin is disabled, the site runs very fast and smooth.

Is there any other way to stop the scan manually?