Your “Identity attribute” which you configured/gave in your SAP HR application configurations. By default IIQ will take that name attribute , I see identity attribute configure as employeeNumber by default it will map the name attribute
https://developer.sailpoint.com/discuss/t/what-is-the-difference-between-identity-attribute-and-display-attribute-and-how-does-correlation-work/73566
If it is helpfull mark as solution