Hi there my friend!
I just had the same issue a few minutes ago but I managed to fix it for my site…
I went to my .htaccess file
DELETE ALL OF THIS BELOW IN IT:
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteRule ^Sign in as Admin/?$ /wp-login.php?wgt2sndnq4pvaw6apu1s2 [R,L]
RewriteCond %{HTTP_COOKIE} !^.*wordpress_logged_in_.*$
RewriteRule ^Administrator/?$ /wp-login.php?wgt2sndnq4pvaw6apu1s2&redirect_to=/wp-admin/ [R,L]
RewriteRule ^Administrator/?$ /wp-admin/?wgt2sndnq4pvaw6apu1s2 [R,L]
RewriteRule ^register/?$ /wp-login.php?wgt2sndnq4pvaw6apu1s2&action=register [R,L]
RewriteCond %{SCRIPT_FILENAME} !^(.*)admin-ajax\.php
RewriteCond %{HTTP_REFERER} !^(.*)radiantplaces.com/wp-admin
RewriteCond %{HTTP_REFERER} !^(.*)radiantplaces.com/wp-login\.php
RewriteCond %{HTTP_REFERER} !^(.*)radiantplaces.com/Sign in as Admin
RewriteCond %{HTTP_REFERER} !^(.*)radiantplaces.com/Administrator
RewriteCond %{HTTP_REFERER} !^(.*)radiantplaces.com/register
RewriteCond %{QUERY_STRING} !^wgt2sndnq4pvaw6apu1s2
RewriteCond %{QUERY_STRING} !^action=logout
RewriteCond %{QUERY_STRING} !^action=rp
RewriteCond %{QUERY_STRING} !^action=register
RewriteCond %{QUERY_STRING} !^action=postpass
RewriteCond %{HTTP_COOKIE} !^.*wordpress_logged_in_.*$
RewriteRule ^.*wp-admin/?|^.*wp-login\.php /not_found [R,L]
RewriteCond %{QUERY_STRING} ^loggedout=true
RewriteRule ^.*$ /wp-login.php?wgt2sndnq4pvaw6apu1s2 [R,L]
</IfModule>
Save the file and refresh your page…. hope this solves it for you as well!