Cannot call WAPI interface '&1' in this context

What causes this issue?

The system returned the call of interface &V1& with an error. The module
&V1& must not be used within the execution of a workflow or work item.

System Response

Call ended with an error. The function was not executed.

How to fix this error?

Remove the call.

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.