@scarlywebs No it’s not a file. By default the plugin goes to the error 404 page. You need to redirect it to your page instead.
Somewhere in Runcloud I would assume there is a function to set up redirects. In cPanel it’s under Domains>Redirects
Look for where you have the option to add a subdomain or addon domain and it will probably be around that area somewhere.
Or maybe there is a totally separate area where you can configure redirects. You’re not looking for a file or a way to modify the plugin, only a function in your account for that domain.
If your server supports .htaccess you could add this to the bottom, changing mysite and mypage to yours:
RewriteCond %{HTTP_HOST} ^mysite.com$ [OR]
RewriteCond %{HTTP_HOST} ^www.mysite.com$
RewriteRule ^wp-login.php$ "https\:\/\/mysite.com\/mypage" [R=301,L]
RewriteCond %{HTTP_HOST} ^mysite.com$ [OR]
RewriteCond %{HTTP_HOST} ^www.mysite.com$
RewriteRule ^wp-login.php\/$ "https\:\/\/mysite.com\/mypage" [R=301,L]