Bug php 8.1

There is a bug occurring in PHP 8.1 version when changing the size of post_max_size it bugs and starts to display this error session_start(): Failed to read session data: files (path: /var/lib/lsphp/session/lsphp81)

Which cyberpanel version are you using?

version 2.3

I think its better to install 2.4.1 as that seems stable to use. In most cases, most of the issues will be fixed as well.