Internal key for relationship is missing

What causes this issue?

To create, change or delete a relationship using an API or BAPI from
iPPE, you must specify the internal identification (GUID). The internal
identification can be determined using the function module
PVSHI_INTERNAL_RELATION_ID.

System Response

The relationship is not created, changed or deleted.

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.

INCLUDE PM_TODO_ALE_CIF OBJECT DOKU ID TX LANGUAGE EN
INCLUDE PM_INTERNER_FEHLER OBJECT DOKU ID TX LANGUAGE EN

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.