Fatal error in 4.6.2

I’m getting a fatal error when adding an item to the cart. PHP error message:

Fatal error: Uncaught TypeError: Argument 3 passed to ADP\BaseVersion\Includes\Core\Cart\CartItem\Type\Container\ContainerPartCartItem::__construct() must be of the type bool, null given, called in /home/xxxx/public_html/wp-content/plugins/advanced-dynamic-pricing-for-woocommerce/BaseVersion/Includes/Compatibility/Container/AbstractContainerCompatibility.php on line 61 and defined in /home/xxxx/public_html/wp-content/plugins/advanced-dynamic-pricing-for-woocommerce/BaseVersion/Includes/Core/Cart/CartItem/Type/Container/ContainerPartCartItem.php:16

Please fix this asap.