The issue is on the QDS side of things, there is still an associated trigger there related to that old task I believe. If you have cleaned things up on the QMS/QMC side, there is a setting you can put in place on one of your QDS nodes that will purge all the stuff that no longer exists in QMS/QMC/QVPR side of things, and that should likely do the trick. I have an Article with a bunch of settings actually:
The one you want is EnableAdvancedFilePurge, just note if you have a QDS cluster setup, you ONLY put this one one of the nodes, not all of them. Hopefully this will do the trick, easiest fix of which I can think and should do the trick. You will need to bounce the QDS service after you add the setting, just FYI.
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