Custom 404 page doesn't appear

RandomUs3r

So i wanted a custom 404 error page. I did everything...texts, image...i even replaced the default 404 URL with my 404 URL.
But when i make it work, it goes to the default 404 page (aka profreehost 404) and no custom 404 page. Unless i type "404.html" on the google search bar.

So am i doing something wrong?