Hi,
Are you using SRM@ERP one client scenario?
If so, please refer to the following doc:
http://scn.sap.com/docs/DOC-49702
If not, you have to check settings in table T77S0(according to note 550055) and check the idoc with t-code we05 to see if there is any error in it. The error should be checked by HR side first.
Best regards,
Ivy
