I hope you removed index.php from your URL, which is done by adding the following rules to the .htaccess file in the DOMAIN root directory or by adding these rewrite rules on virtual hosts.
, url index.php? params, , url "index.php ", PHP- , CI .
.htaccess "assets" , index.php
RewriteEngine on
RewriteCond $1 ^!(index\.php|assets)
RewriteRule ^(.*)$ /index.php?$1 [L,QSA]