No valid header?

Updated from WordPress 6.5 to 6.6.2 and then get a message that autodescription/autodescription.php has been deactivated because it doesn’t have a valid header. Huh? Had to google what autodescription was and it brought me here. This plugin is no longer even listed on my Plugins page. Not just deactivated but removed. But the whole folder is still on my server. I thought I would just re-install it, but when I try I get an error that the Destination folder already exists. Why not overwrite it?

Is there any way to re-install this plugin without losing my settings and all the SEO I’ve already manually done? Or do I have to remove that folder and install fresh?

Thanks!