Categories in products and object (error COM_HIERARCHY 001)

Hello,

I need to assign to a product or to an object multiple values of the same hierarchy XYZ. The hierarchy is not to be replicated in ECC.

I get the error COM_HIERARCHY 001 (Hierarchy XYZ is used more than once): is there any customizing/workaround to prevent this error message ?

If this is not possible, have you any suggestion on how to create a similar classification system for products and objects ?

Thank you and Regards

Roberto