Symptoms
When running AutoSSL, the following is reported where example.tld is your domain name, and $IP is the IP address the domain resolves to:
The domain “example.tld” resolved to an IP address “$IP” that does not exist on this server
Description
In order for HTTP validation to pass, the domain needs to either resolve to the IP address that the cPanel account is configured to use on the server, or to a proxy that proxies to the account IP address.
Workaround
Configure the domain to resolve to an IP address that exists on the server that AutoSSL is running on or exclude the domain from AutoSSL.