Basically it's usually because your Cpanel has new IPs and the old IPs it knows are no longer available/working/valid.
The solution is to change the site's IP but you may run into issues for various reasons. Here is what I encountered below.
It redirects there even though public_html is empty and doesn't have any index or htaccess redirect.
This issue happened after a CPanel migration, the site is being set to an old IP, this is the problem.
You need to use the "Change Site's IP Address" feature.
Changing ip for thedomain.com (thedomain) to ip.ip.ip.ip
Setting up for ip change..... Done
Sorry, ip.ip.ip.ip is in use by another domain name and is not a shared ip.
1. You need to change root's shared IP
"Basic cPanel & WHM Setup"
2. Then change the site's IP address.
3. Then restart Apache
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