Values for characteristic &2 already locked by user &1

What causes this issue?

Characteristic values for characteristic &V2& are to be locked.
However, one or more of the values are already locked by user &V1&.

System Response

The object can only be displayed.

How to fix this error?

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

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.