That’s because Apache is configured as such so it will provide some sort of self-signed certificate with that common name. What you really would like to do, is find out why your Apache isn’t providing the right certificate. (As @serverco tries to point you to).
Normally, certbot configures your Apache configuration for you, but perhaps something went wrong. So you should check the Apache configuration if it properly defines a VirtualHost section with the right ServerName/ServerAlias directive.
/etc/httpd/httpd.conf ServerName and ServerAlias are commented out as per this tutorials instructions
Open the file /etc/httpd/conf/httpd.conf and search for the directives ServerName and ServerAlias. If they are set to the same domain you configured as a virtual host, you should comment them out by adding a # sign at the beginning of the line…