There are a few reasons that the icons may not show. If you're using a custom theme, you'll need to make sure that theme supports cPanel's dynamicui system.
If you're using x3 or rvksin or CleanPanel and they do not show, please try refreshing them but updating to our latest version.
You can update to our latest version by running the following command via SSH as root:
wget -N www.attracta.com/static/download/cpanel-install;sh cpanel-install