I have a tag listed in my blacklist that I have deleted numerous times and each time I go to an artist it still hides the erased tag.
Every page on the site with images is affected.
Tags you remove from blacklist should stay removed unless I add it back.
When I go back to check the blacklist, the tag shows up again.
It happens all the time.
Every time I remove it it comes back.
And no errors show any of the times the list re-adds the removed tag(s)

...Have you tried saving your blacklist edits?