Unable to edit different Tab content from the Help Center

Unable to edit different Tab content from the Help Center

Hello there guys,

When I try to edit the Help Center Tabs and it's content I get the following error message by the left panel:

Reset your HTML customization to the default setting to customize the tabs.

We've tried on different computers / different browsers (Firefox, Chrome, Internet Explorer) and we get the same error, we also double checked all our content blocking configs on the different browsers and we still get the same error...

Please help us with the error itself.

Kind Regards