found in version 12.1.5
in <SEPM>\Php\Include\Util\util.php
line 22
add a missing include in:
require_once("Include/scans/ScanTypes.php");
$scanTypes=ScanTypes::getInstance();
result
require_once("Include/scans/ScanTypes.php");
include_once("Include/Inventory/I18nInventory.php");
$scanTypes=ScanTypes::getInstance();