Slow performance OCS NG SERVER 2.6 UNIX

Have installed OCS NG server 2.6 on RHEL 7.7 server with ocsinventory-server 2.6.0.2/ocsinventory-reports2.6.0.2 and PHP 7.4 (and extensions), all it's okay but on the web GUI, there's an extreme slowly performance on each actions -> page load in 20 secondes.

Have tuned mysql with phpmyadmin, restart httpd/mariadb, reboot server and any changes.

Anyone with same problems and solved?

thanks by advance