Newly created cPanel accounts are provisioned with an IP address that either no longer exists on the server or simply is not the one the administrator wants as the default shared vhost IP.
If you recently had an IP modification in your server involving the shared vhost, you must update the shared vhost entry within the WHM configuration. If this step is not performed after any IP modifications will cause any new accounts being created to be provisioned with the IP address that is still listed as the default shared vhost.
You can quickly check the default shared vhost IP addresses that are configured using this command.
grep ADDR /etc/wwwacct.conf
To address this you will have to update the default shared vhost IP addresses via the following interface:
WHM >> Server Configuration >> Basic WebHost Manager
Then locate the appropriate options for IPv4 or IPv6:
The IPv4 address (only one address) to use to set up shared IPv4 virtual hosts.
The IPv6 address (only one address) to use to set up shared IPv6 virtual hosts.