logging on reverts back to /wp-admin/ page

Hi,
I have had no issues until recently with this plugin. But now when i enter my login url for wps hide login: e.g. https://www.apis.de/my_custom_url_admin it redirects to https://www.apis.de/wp-admin page and simply says “This page has been disabled”. I then have to login to my server and mv the plugin temporarily to get access to my admin.
Any suggestions?
Thx in advance

The page I need help with: [log in to see the link]