2905590 - [attribute] is not available in content, but is required in defined system transformation

Identity Provisioning service (IPS) job fails with a similar error:

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"errorMessage": "\nuser:<user>,\n\nsystem=<system>,\n\nerror=com.sap.security.iag.provisioning.mapping.exceptions.InvalidJsonContentException: Source path: $['urn:sap:cloud:scim:schemas:extension:sfsf:2.0:User']['userId'] is not available in content, but is required in defined system transformation
Caused by: com.sap.security.iag.provisioning.mapping.MandatorySourcePathNotFoundException: Source path: $['urn:sap:cloud:scim:schemas:extension:sfsf:2.0:User']
['userId'] is not available in content, but is required in defined system transformation Caused by: com.jayway.jsonpath.PathNotFoundException: No results for path: "

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This is a generic KBA for possible next steps for advanced users. Check See Also part below for concrete properties.

Identity Provisioning

IPS, not available in content, required in defined system transformation, source, target, transformation, rule , KBA , BC-IAM-IPS , Identity Provisioning Service (IPS) , Problem