Data import - update existing employees

Hi.

When I try to import employees through Data Import tool, I get following error: Employees: Value in field Personnel number must be unique. Object Lastname, Firstnamealready has this value (5363657226). It is true that an employee with the same Personnel number exists. Data Import should just update that person if data has changed in HRM.

I have also set search criteria to Personnel Number <> Employee number. What could be wrong? Did I miss something?

Thanks.

Evgen