When you use 'Dynamic item filter' in an LPG, it can happen that a product is left out because it does not match the filter criteria any more. Then the corresponding PGI line item gets deleted automatically from the LPG – but only if this item is not in the Submitted status.
If you need to have PGIs even in the Submitted status auto deleted, use the /wiki/spaces/UDEV/pages/1716191397 'allowAutoDeletionOfSubmittedPGI'.