The Softaculous Team has launched Softaculous 5.1.5 in Stable branch
1) [Bug Fix] : On cPanel servers when the permission for Softaculous
binary was incorrect, Softaculous was starting multiple processes. This
is fixed now.
Incorrect binary permission Child failed to make LIVEAPI connection to cPanel.
Just Execute these commands at your server
chown root:root /usr/local/cpanel/whostmgr/docroot/cgi/softaculous/bin/soft
chmod 4555 /usr/local/cpanel/whostmgr/docroot/cgi/softaculous/bin/soft