Message type: E = Error
Message class:  COM_PRODUCT_CUST - General Customizing Messages for Product Master 
Message number: 016
Message text: Product type & has a different product type as reference product type
You tried to change the assignment to the application <LS>Product</>
for product type &v1&.
This is not permitted as this product type has another product type as
the reference product type.
The system issues an error message and will not allow you to continue with this transaction until the error is resolved.
If you do want to change this assignment, ask your system administrator
to change the Customizing settings for number assignment. The product
type &v1& must not have another product type as the reference product
type.
You can maintain a reference product type for number assignment using
transaction <DS:TRAN.COMCPRTYPENRO>COMCPRTYPENRO</>.
Error message extract from SAP system. Copyright SAP SE.
The SAP error message COM_PRODUCT_CUST016 indicates that there is a mismatch in the product type of a product you are trying to create or modify in relation to its reference product type. This typically occurs in the context of SAP's Product Lifecycle Management (PLM) or similar modules where product types are defined and managed.
Cause: The error arises when: You are trying to create or change a product that has a different product type than the one defined for its reference product. The reference product type is set up in a way that it expects a specific product type, and the product you are working with does not conform to that expectation.
Solution: To resolve this error, you can take the following steps: Check Product Type Configuration: Verify the product type of the reference product. You can do this by navigating to the product master data and checking the attributes of the reference product. Ensure that the product type
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COM_PRODUCT_CUST015 & is already being used as a reference product type for number assignment
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