Updating Secure Ports: Changes Do Not Save

I am trying to update the HTTPS port as outlined in the "How to Setup the Sangoma Phone Desktop Client on the PBX" support article, but when I click the update now button, it always reverts back to the disabled settings that were there prior. The only Secure Port that does not revert to disabled is for the Admin service, but that was enabled prior to attempting to setup the desktop client. FYI: This system is PBXact not FreePBX but to my understanding is that they are identical except for the branding and licensing.