More than one object already classified with same characteristic values

What causes this issue?

A number of objects with the same characteristic value were already
classified with class '&V1&' of class type '&V2&'. In class maintenance,
it was defined that a warning message appears in this case. This draws
your attention to potential redundancies.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Check the characteristic value.
If you do not change the value, you are explicitly allowing
redundancies. However, the object to be classified may not be necessary,
because it can be replaced by the objects that already exist.

Error message extract from SAP system. Copyright SAP SE.