htaccess domain access without file endings - .htaccess

Question

I want domain.de/test.php to appear without the .php.
I tried this, but its not working. Is there a conflict maybe?
This is my full .htaccess now. Do I have an error somewhere or conflict?
RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule . / [L,R=301]
# FORCE HTTPS
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://bm-translations.de/$1 [L,R=301]
RewriteCond %{HTTP_HOST} ^www\.(.*)$ [NC]
RewriteRule ^(.*)$ https://%1/$1 [R=301,L]
RewriteCond %{HTTPS} !on
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
#remove the need for .php extention
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^(.*)$ $1.php
<IfModule mod_filter.c>
<IfModule mod_deflate.c>
## Enable gzip compression ##
# compress text, HTML, JavaScript, CSS, and XML
AddOutputFilterByType DEFLATE text/plain
AddOutputFilterByType DEFLATE text/html
AddOutputFilterByType DEFLATE text/xml
AddOutputFilterByType DEFLATE text/css
AddOutputFilterByType DEFLATE application/xml
AddOutputFilterByType DEFLATE application/xhtml+xml
AddOutputFilterByType DEFLATE application/rss+xml
AddOutputFilterByType DEFLATE application/javascript
AddOutputFilterByType DEFLATE application/x-javascript
# Remove browser bugs
BrowserMatch ^Mozilla/4 gzip-only-text/html
BrowserMatch ^Mozilla/4\.0[678] no-gzip
BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
Header append Vary User-Agent
## END Enable gzip compression ##
</IfModule>
</IfModule>
AddType font/woff .woff
ExpiresByType font/woff "access plus 1 year"
AddOutputFilterByType DEFLATE font/woff
AddType image/svg+xml .svg
AddOutputFilterByType DEFLATE image/svg+xml
## EXPIRES CACHING ##
<IfModule mod_expires.c>
ExpiresActive On
ExpiresDefault "access plus 3 month"
ExpiresByType image/jpg "access 3 month"
ExpiresByType image/jpeg "access 3 month"
ExpiresByType image/gif "access 3 month"
ExpiresByType image/png "access 3 month"
ExpiresByType image/svg+xml "access 3 month"
ExpiresByType text/css "access 3 month"
ExpiresByType text/html "access 3 month"
ExpiresByType application/pdf "access 3 month"
ExpiresByType text/x-javascript "access 3 month"
ExpiresByType application/javascript "access plus 3 month"
ExpiresByType application/x-shockwave-flash "access 3 month"
ExpiresByType image/x-icon "access 3 year"
ExpiresDefault "access 3 month"
</IfModule>
## EXPIRES CACHING ##
I tried to put the part with file-extension on top and at the bottom, but everywhere its not working.

Answer 1

You may use these rules in site root .htaccess:
RewriteEngine On
# remove www and redirect http to https
RewriteCond %{HTTP_HOST} ^www\. [NC,OR]
RewriteCond %{HTTPS} !on
RewriteCond %{HTTP_HOST} ^(?:www\.)?(.+)$ [NC]
RewriteRule ^ https://%1%{REQUEST_URI} [R=301,L,NE]
# To externally redirect /dir/file.php to /dir/file
RewriteCond %{THE_REQUEST} \s/+(.+?)\.php[\s?] [NC]
RewriteRule ^ /%1 [R=301,NE,L]
# internally add .php extension
RewriteCond %{REQUEST_FILENAME}.php -f
RewriteRule ^(.+?)/?$ $1.php [L]

Answer 2

Solution was to add RewriteBase /
RewriteEngine on
RewriteBase /
# FORCE HTTPS
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://bm-translations.de/$1 [L,R=301]
RewriteCond %{HTTP_HOST} ^www\.(.*)$ [NC]
RewriteRule ^(.*)$ https://%1/$1 [R=301,L]
RewriteCond %{HTTPS} !on
RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
#remove the need for .php extention
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^(.*)$ $1.php
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule . / [L,R=301]