An unexpected error occurred (can you help me fix?)

That worked perfectly. Thanks for sticking with me on this! But I made the changes in another domain, and it’s (a) not redirecting from http and (b) displaying a warning from https. Here’s its file:

image

It looks like it is set correctly:

curl -Iki http://computingunplugged.com/x/y/z
HTTP/1.1 301 Moved Permanently
Date: Sun, 17 May 2020 03:05:14 GMT
Server: Apache/2.4.18 (Ubuntu)
Location: https://computingunplugged.com/x/y/z
Content-Type: text/html; charset=iso-8859-1

Perhaps your browser has cached that a previous page.
Try clearing your cache or using a different browser.

The security warning is because it gets redirected to www.computingunplugged.com
But the cert doesn’t cover that name:

So there is some other redirection in effect.
Is should NOT have gone to WWW.

Do you have an .htaccess file or any other redirection in place?

And since things have changed, please show the current:
certbot certificates
apachectl -S