SAP Message 54590 - Personnel number cannot be locked for payroll

Diagnosis
The personnel number cannot be locked for payroll because there isalready a payroll result for the current payroll period and the payrollstatus in the control record has not been set to "exit".

Procedure
If you want to lock the personnel number for payroll in the currentpayroll period, you must use transaction PU01 to delete the payrollresult that exists for this period.