404 not redirecting a unknown php file

I'm using LAMP Apache with CentOs 6.9

My site is abcd.xyz.com that type sub-domain also it hosted on a Virtual host.

When I wrote abcd.xyz.com/hshgdgd or abcd.xyz.com/hshgdgd.ht, it redirecting 404 page fine but when I wrote extension .php like abcd.xyz.com/hshgdgd.php, it's not redirecting just telling File not found.

My .htaccess below:

RewriteEngine On
ErrorDocument 404 xyz.com
ErrorDocument 402 xyz.com
ErrorDocument 403 xyz.com
ErrorDocument 500 xyz.com

mod rewrite it on/allow my domain root folder in httpd.conf.