Template &1 is used in relationship; changes cannot be reversed

What causes this issue?

The template &V1& is used in an inheritance relationship.
You can therefore only change the inheritance template in such a way
that it does not restrict the criteria that are passed on. You should
always consider the consequences for the target specifications when you
change the inheritance template.

How to fix this error?

Check whether the changes to the inheritance template already in use
are necessary. If you want to change the inheritance template in such a
way that the data passed on would be restricted, you must first delete
the inheritance template from the corresponding inheritance
relationships.
<ZH>Additional information</>
INCLUDE EHS_SAF_27A_INHERIT_USED OBJECT DOKU ID TX
You can also only change criteria that have already been changed and
saved if you observe these rules. In particular, the <LS>All
identifiers</> and <LS>All usages</> indicators cannot be reset once
they have been saved. In this sense, changes are <ZH>irreversible</>.

Error message extract from SAP system. Copyright SAP SE.