Inspection code is missing; item &1/&2

What causes this issue?

The inspection code is missing.

System Response

The inspection is incomplete and cannot be confirmed.
This only applies to inspections in the warehouse; inspections by the
supplier do not require confirmation.

How to fix this error?

Specify an inspection code.

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.