Message type: E = Error
Message class:  HUGENERAL - Handling Units - Packing 
Message number: 013
Message text: &1 is a packing proposal in a sales document, not an HU
Handling unit &V1& could not be found. A packing proposal in a sales
document was the only object found with this number.
It is not possible to assign packing proposals to packing-data
processing.
Make changes to packing proposals by processing the sales document.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message HUGENERAL013 indicates that there is an issue with a packing proposal in a sales document. Specifically, the error states that the item in question is a packing proposal and not a Handling Unit (HU). This can occur in scenarios where the system expects a Handling Unit but instead encounters a packing proposal.
Cause: Incorrect Document Type: The sales document may be referencing a packing proposal instead of a Handling Unit.
Configuration Issues: There may be configuration settings in the SAP system that are not aligned with the expected handling unit processes. Data Entry Errors: There could be mistakes in the data entry where a packing proposal was mistakenly created or referenced instead of a Handling Unit. Process Flow Issues: The process flow may not be correctly set up to handle the transition from packing proposals to Handling Units.
Solution: Check Document Type: Verify that the sales document is correctly set up to use
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