Message type: E = Error
Message class:  KZ - Cost Object Repetitive Mfg / Process Mfg 
Message number: 708
Message text: No lower-level product groups are assigned to product group &
No product groups are assigned to <DS:GLOS.CO_product_group>CO product
group</> &v1&.
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 KZ708 indicates that there are no lower-level product groups assigned to the specified product group. This typically occurs in the context of product group hierarchies in SAP, particularly in the areas of Sales and Distribution (SD) or Material Management (MM).
Cause: Missing Assignments: The primary cause of this error is that the product group you are trying to work with does not have any lower-level product groups assigned to it. This can happen if the product group was created but not properly configured. Hierarchy Structure: The product group hierarchy may not be set up correctly, leading to a lack of lower-level groups. Data Entry Errors: There may have been an oversight during the data entry process, where lower-level product groups were not assigned.
Solution: Check Product Group Configuration: Navigate to the product group configuration in SAP (Transaction Code: OVZG for product group maintenance). Verify that the product group in question has lower-level product groups
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