Upon logging into PKI Manager, select "Manage certificate profiles" icon or use the blue cog icon to manage certificate profile:
From the manage certificate profile menu, click and select the profile that you would like to modify the email templates for:
On the right-side column of the certificate profile, you should see several sections that include the “Customize certificate notifications” section; click "Edit":
You can edit any of the templates available for the given profile, in this case, you have 7 templates that can be modified. In this case, we modified the “Renewal reminder” template, then hit save.
After you hit save you will see this at the top of the profile, meaning you successfully saved the changes: