Diagnosis
V1 is used in hierarchy v2 in hierarchy version v3 starting onV4. therefore you are not allowed to delete v1 v2. deletionis only possible when the characteristic value is no longer used.

Procedure
If you want to delete &V1&, you first have to change the hierachy sothat &V1& is not used any more.
There may still be other uses of &V1&. The system could show another usewhen you again try to delete after changing the hierarchy. You have todelete all uses that are displayed. You can only delete &V1& after that.