Some few AVX512 tasks become stuck at certain point during crunching. If nothing is done they usually end in error by exceeding elapsed time limit, the wingmen units use to finish properly.
https://escatter11.fullerton.edu/nfs/workunit.php?wuid=368809704
https://escatter11.fullerton.edu/nfs/result.php?resultid=399169443
https://escatter11.fullerton.edu/nfs/result.php?resultid=399167913
https://escatter11.fullerton.edu/nfs/result.php?resultid=399152353

If they are paused before ending in error and restarted, they resume computation at some previous point and this time they can finish properly or get stuck again like this one that I've finally aborted
https://escatter11.fullerton.edu/nfs/result.php?resultid=399302079

I've seen this happening in other hosts crunching AVX512 units, intel and amd. Always just very few units.