When you enable Clickjack protection within your Salesforce organization, in Salesforce Summer '15 release and later, Visualforce custom console and homepage components are unsupported by the platform. This limitation means that the NewVoiceMedia Vonage Contact Center console component, Log a Call (introduced as an enhancement in version 18.205), no longer works. For this reason, we cannot support Log a Call as a console component in within Salesforce Classic.
...