.htaccess works with HTML but doesn't work with PHP

I am having a problem with my .htaccess file. I use Apache2 on my Ubuntu 20.04. I want to rewrite URLs to my PHP file. And I have followed How To Use the .htaccess File and How to Rewrite URLs with mod_rewrite for Apache on Ubuntu 20.04 tutorials.

The problem is when I enter my /home page, it does not found. While I can still enter /home.php. However, it works with HTML, both /about.html and /about pages work.

Here is my .htaccess file.

RewriteEngine on

RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^\.]+)$ %1.php [NC,L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^([^\.]+)$ %1.html [NC,L]

I would appreciate any help! Thank you.