Long Service Leave - existing employee

Have 2 existing employees who need to have LSL set up in their cards.  LSL is already set up in MYOB as a payroll cateogory.  1 employee started 2005 other in 2015 (both full time 38 hours per week). MYOB online chat were not helpful in working out how to enter the hours accrued into MYOB.
Has anyone done this previously and who could advise me how to do this. Thanks  :-)