The customer reported that a specific custom field group was missing from the post edit screen.
Solution:
The post field group was available, but since the section was part of the accordion, the arrow next to it needed to be clicked, in order to open/collapse it.
The problem here is that the user is getting the following error.
PHP Fatal error: Uncaught Error: Class 'OTGS\Toolset\Access\Controllers\UploadPermissions' not found in .../wp-content/plugins/types-access/application/models/capabilities.php:613