Problem
In the popup, no items can be added to the shipment if it requires customs information. Nothing happens when clicking "Add products to package".
Further details:
- In the browser console an error HTTP 500 occurs when calling "getShippingItemsGrid".
- The log says:
"PHP Fatal error: Uncaught Error: Call to a member function isStatic() on boolean in /var/www/html/vendor/magento/module-eav/Model/Entity/Collection/AbstractCollection.php" - Stack trace (excerpt):
#0 /var/www/html/vendor/magento/module-catalog/Model/ResourceModel/Product/Collection.php(640): Magento\Eav\Model\Entity\Collection\AbstractCollection->addAttributeToSelect('dhl_dangerous_g...', true)
No products shown after clicking
"Add products to package"
Cause
The Stack trace indicates that the product attribute "dhl_dangerous_goods_category" does not exist in the system. Usually, it should have been created automatically.
Solution
Create the missing attribute in "Stores -> Attributes -> Product Attributes -> dhl_dangerous_goods_category".