i am trying to make a blog for which i have category/subcategory/then-all-the-posts

till category/subcatedory/ everything is fetching data properly but then click on the slup from data.php i get category not found this wrroe message is in subcategories.php

here is my htaccess

 RewriteEngine On
 RewriteBase /blog/


 RewriteCond %{REQUEST_FILENAME} !-f
 RewriteCond %{REQUEST_FILENAME} !-d
 RewriteRule ^([^/]+)/?$ subcategories.php?cat_slug=$1 [L,QSA]


 RewriteCond %{REQUEST_FILENAME} !-f
 RewriteCond %{REQUEST_FILENAME} !-d
 RewriteRule ^([^/]+)/([^/]+)/?$ data.php?cat_slug=$1&subcat_slug=$2 [L,QSA]


 RewriteCond %{REQUEST_FILENAME} !-f
 RewriteCond %{REQUEST_FILENAME} !-d
 RewriteRule ^(.*)$ posts.php?post_slug=$1 [L,QSA]

could someone see why posts.php is not being able to access the slug?