SSL gone "self-signed" on main WHM installation breaking email clients

[eugenevdm.host]

The scenario a WHM host with many cPanel domains is called:

host.whm-example.com

Many of the actual clients are not using `mail.domain-name.com` as their email server, but rather the main hostname, `host.whm-example.com`

I know, this is not how it's done but it's been like that for years and it's worked.

Then boom! Suddenly today the main host installation decides it's going to install a self-signed certificate.

Now every single email client is getting a certificate warning.

I want to make sure the main host just renews itself like it's done for years but whatever certificate that always just worked.

We have multiple A record for the hostname, I suspect this is a clue.

I cannot deduce from the WHM user interface how to install a free certificate. I don't want to buy one for the main installation.

We use Let's Encrypt, but I'm not sure if the main installation uses that.

The screenshot gives a clue where I'm stuck.

 

[cPanelAnthony]

Hello! Could you open a ticket using the link in my signature so we can take a closer look? Provide me with the Iicket ID if you can.