Hi Vijay,
There may be several reasons why they get out of synch, but you can try running report RHINTE20. The description of the report (below) seems relevant.
RHINTE20 Description:
This program can be used to check whether the relevant object types for
integration have been created in both Personnel Administration (HR-PA) and
Personnel Planning and Development (HR-PD).
The entries in the HR tables T513/T513S (job), T528B/T528T (position, work
center) and T527X (organizational unit) are compared with the corresponding
objects that have been created in the HRPnnnn file for PD in the integration
plan version.
Objects that are missing either in PA or PD can be created immediately.