Can't turn off password protect all posts plugin, WP password protection not wor

I installed the password protect all posts plugin, decided it didn’t work for my purposes (type in a password to see any and every post, yet the titles still show up? Nah.), and deactivated it. Afterward, all posts were still password protected. I deleted the plugin, cleared the cache, tried it on different browsers and machines, to no avail. How the heck do I back out of this? Do over! ??

The reason I did this in the first place was that WPs built-in password protection (on the page I wanted to protect, which is my “posts” page) did not seem to be working, again, even after clearing caches and trying on virgin browsers that had never seen this site before. Does anyone have any suggestions on what I’m doing wrong?