Generally, once you create the cert your server configuration needs update to use that cert and then needs to be reloaded / restarted to take effect. It seems like one or more of these things did not happen.
If you provided details of your server and oper sys we could be more specific. I do not wish to interact via email or PM but others may.
Also, there are consultants who offer paid assistance. This is an alternative approach if you are unwilling to share details in this forum.