ErrorDocument 404 and Redirect 301 not working into htaccess

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1

Below I use htaccess configuration for 404 handling and redirect 301 to new url but not working. Cyber panel Latest Build: 5.

I tried best on my level but not get success. I have 2 VPS server same issue on both cyberpanel.

RewriteEngine On
RewriteCond %{HTTPS} off

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d

ErrorDocument 404 /404[.]html