Message type: E = Error
Message class:  VHUMI - Messages for material identification 
Message number: 021
Message text: Different batches are packed for reservation &1/&2
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
See your system administrator or create an OSS message!
Error message extract from SAP system. Copyright SAP SE.
The SAP error message VHUMI021 indicates that there is a discrepancy between the batches that are being packed for a reservation. Specifically, it means that different batches are being used for the same reservation, which is not allowed in the context of the operation you are trying to perform.
Cause: Batch Management: The system is configured to manage batches, and the reservation you are trying to process is linked to a specific batch. If you attempt to pack items from different batches for the same reservation, this error will occur. Incorrect Batch Selection: The user may have selected items from different batches inadvertently.
Configuration Issues: There may be configuration settings in the batch management or inventory management that are causing this issue.
Solution: Check Batch Assignment: Verify the batches assigned to the items in the reservation. Ensure that all items being packed belong to the same batch. Adjust Reservation: If you need to pack items from different
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