Specification &1 is currently used in &2

What causes this issue?

You attempted to delete the specification &V1& that is currently still
being used in &V2&.
In principle, specifications can be being used in the following objects
or for the following purposes:
The specification is used by another specification as a reference
specification.
The specification is part of the composition of another specification.
The specification is part of a specification listing (for example,
<LS>BAT value</>).
The specification is used in an inheritance relationship.
The specification is used in a customer-specific usage.
The specification is used by a report.
The specification is used by a transport classification or dangerous
goods classification.
The specification is used in a risk assessment.
The specification is used by an exposure assignment.
The specification is used by an exposure profile entry.
The specification is used by an object assignment in HR (for example,
exposure group or position).
The specification is used in a health surveillance protocol.

System Response

The specification is not deleted because it is still being used.

How to fix this error?

Run the where-used list for specifications to find out which object is
using the specification.

Error message extract from SAP system. Copyright SAP SE.