3585576 - Error "Number range XX is internal, do not enter a personnel number" in app Migrate Your Data

In Migration Cockpit, when simulating data by object "HCM - Employee" (SIF_HCM_EMPLOYEE), the following error occurs when the personnel number is filled in the template:

"Number range XX is internal, do not enter a personnel number"

However, if "Personnel Number" is not entered, an error message will appear during file validation: 

"Sheet YYY, field Personnel Number, row Z is empty; enter value for the mandatory field"

SAP S/4HANA

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