Message type: E = Error
Message class:  VL -  
Message number: 164
Message text: Delivery already contained in a shipment
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
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The SAP error message VL164 ("Delivery already contained in a shipment") typically occurs when you attempt to add a delivery to a shipment that has already been included in another shipment. This can happen in the logistics and shipping processes within SAP, particularly when managing deliveries and shipments in the Sales and Distribution (SD) module.
Cause:
Duplicate Inclusion: The delivery you are trying to add has already been included in a shipment.
Incorrect Shipment Processing: There may be an attempt to process a delivery that is already associated with a different shipment.
System Configuration: There might be issues with how the system is configured to handle shipments and deliveries.
Solution:
Check Shipment Status: Verify the status of the shipment to which the delivery is already assigned. You can do this by navigating to the shipment document in SAP and checking the list of deliveries included.
Review Deliveries: Go to the delivery document and check if it is
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