Hello,
i have exactly the same problem, all my subpages are shown as noindex in the google search console.
The password protected links still work after I uninstalled the plugin, or they also refer to the start page.
Cache is cleared.
Robots.txt is on index
htaccess is also correct.
The source code also shows index.
But still all subpages are shwon in the Google Search Console on noindex since I started using the plugin and even after I deleted it.
I would be really grateful for help.
Kind Regards
