Hi Ritesh,
please do these things
use call function 'BAPI_EMPLOYEE_ENQUEUE'
before using CALL FUNCTION 'HR_INFOTYPE_OPERATION'
and after that the CALL FUNCTION 'HR_INFOTYPE_OPERATION'
and after that use BAPI_EMPLOYEE_DEQUEUE
use BAPI_TRANSACTION_COMMIT to commit your work.
And see if the return values are 0 , that means data changes has been done..