Regarding sec 87/a in tds return

I HAVE FILED MY 4TH QUATER TDS RETURN ON 12/4/2014. IN TDS RETURN I REPORTED MY ONE EMPLOYEES YEARLY TOTAL TAXABLE INCOME RS.460393/- & REPORTED TAX DEDUCTED AS 24760/- BUT TODAY I RECEIVED DEMAND NOTICE AS THEY SAID TDS TO BE DEDUCTED AS RS.24820.48/-.

MY QUESTION IS AS PER INCOME TAX DEPARTMENT 2000/- REBATE U/S 87A HAS TO BE DEDUCTED FROM BASIC TAX WHICH IS 26039/- AND THAN AFTER ON REMAINING RS.24039/- E.C.(2%) & SHEC(1%) CALCULATED SO WE GOT NET TAX PAYABLE AS 24760/-. I ALSO ATTACHED TAX CALCULATION SCREEN SHOT.

IN JUSTIFICATION REPORT THEY SAID SORT DEDUCTION OF RS.60.48/-. HOW ITS POSSIBLE. IN INCOME TAX EFILING PORTAL TA CALCULATOR SHOW ME NET TAX PAYABLE AS RS.24760/- .

THAN HWO CORRECT TDS CPC DEPARTMENT OR INCOME TAX E-FILING PORTAL CALCULATION..

PLEASE SOLVE MY CONFUSION AS SOON AS POSSIBLE..