St liability for discount of freight amount

IN TAX INVOICE OF PURCHASE OF GOODS THERE IS A FREIGHT CHARGES INCLUDED AND  SEPRETALY GIVEN ,BUT THE SAME AMOUNT IS GIVEN AS DISCOUNT , SO NOW IS THERE ANY LIABILITY TO PAY SERVICE TAX  BY CONSIGNEE ON 25% OF SUCH AMOUNT CONSIDERING REVERCE CHARGE MECHANISM , AS THERE IS SPECIFIC NOTE ON BILL THAT" ST ON FREIGHT PAYABLE BY CONSIGNEE"

AND IS THERE ANY LIAB. IF I AM NOT PAYING ST ON THE SAME , BY TREATING IT AS DISCOUNT.

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