Plugin settings. Error accessing the admin panel at [sitename.tld/admin/]

Hello,

I installed your plugin to change the path to the WP theme and the path to the css-files of the WordPress theme. Before installing the plugin, I could log into WordPress Control Panel at [sitename.tld/ADMIN/]. After activating the plugin, I cannot enter the admin panel at the specified address [/ADMIN/] – an error 404 appears. If I enter the address [sitename.tld/WP-ADMIN/], then I can enter the panel.

I was not going to hide the admin panel and change its paths in the plugin settings. And I did not change the settings associated with the Admin URL and wp-login.php.

I changed only 4 settings through the plugin – New Theme Path, New Style File Path, 1Remove description header from Style file, Remove Other Generator Meta.

If I disable the plugin, then I can again enter the admin panel at [sitename.tld/ADMIN/]

Cache plugin is turned off, browser cache is cleared
There are no caching extensions on the hosting, such as Varnish, etc.
WordPress 4.9.8
WP Hide & Security Enhancer 1.5.1.2
PHP 7.1.22
.htaccess is used with default settings + WP Hide & Security Enhancer plugin settings, which are recorded in .htaccess