When using the WHM interface to update the "Certificate Authority Bundle" of an SSL certificate, the installation will not update and not produce an error.
Using the WHM interface, WHM: Home »Service Configuration »Manage Service SSL Certificates, to view a hostname SSL certificate by clicking the "Apply Certificate to Another Service" link, you will see the SSL cert shown below in three text boxes.
Certificate Authority Bundle
Updating the 'Certificate Authority Bundle' box with new certificates may fail silently, without notification.
For reference, the case number is CPANEL-33152. Follow this article to receive an email notification when a solution is published in the product.
There is not a workaround at this time.