Action &1 exists at characteristic &2 at material &3

What causes this issue?

The mentioned action is used in the configuration model.

System Response

The use of actions may have a negative effect on the performance; see
note 917987. Therefore, it is generally not recommended to use actions.

How to fix this error?

If possible, replace actions by other dependencies (e.g. procedures) -
at least when performance issues exist.

Procedure for System Administrators

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

Error message extract from SAP system. Copyright SAP SE.