(1) Where a tax invoice has been issued for any sale of goods but if within six months from the date of such sale, the amount shown as tax charged in such tax invoice is found to exceed the tax payable, the registered dealer effecting the sale shall immediately issue to the purchasing registered dealer a credit note containing such particulars as may be prescribed.

(2) Where a tax invoice has been issued for sale of any goods and the tax payable in respect of the sale exceeds the amount shown as tax charged in such tax invoice, the registered dealer making the sale, shall immediately issue to the purchasing registered dealer a debit note containing such particulars as may be prescribed.

(3) Any registered dealer who receives or issues a credit note or a debit note shall modify his return for the period in which the credit note or debit note is received or issued, as the case may be, and pay any tax due before furnishing such return.