Absence days calculating as pay days.

Hi Experts,

1) one employee was absent in the month of march  18.02.2013 to 26.02.2013 and 28.02.2013 to 08.03.2013(18 Days) he got paid only for 13 days( we are using fisacl year calendar 12 th period is 16th feb to march 15)

Calendar days 31 - Absence days 18= 13 days (salary)

2) same employee was absent in the month of April 31.03.2013 to 15.04.2013 (16 Days) he got paid for 14 days only

Calendar days 30 days - Absence days 16 days = 14 Days (salary)

Problem is

3) Same employee was absent entire month in the may,User has maintained 2 record's in the absence info type

   A) 16.04.2013 - 15.05.2013 (Entire month 31 days)

   B) 02.05.2013 - 15.05.2013 (13 days)

   31 + 13 = 44 days Absence was maintained by user

  Now system is calculating 44 days as paid and salary is processing when executing the payroll cycle.

What could be the reason please suggest me.

Thanks

Venkatesh