“(1) Where a person has (whether before or after the commencement of this Act) paid an amount to the Commissioners by way of VAT which was not VAT due to them, they shall be liable to repay that amount to him.… (4) The Commissioners shall not be liable, on a claim made under this section, to repay any amount paid to them more than three years before the making of the claim…”
“Where the Commissioners – (a) Have assessed a person to VAT for a prescribed accounting period (whenever ended), and (b) In doing so, have brought into account as output tax an amount that was not output tax due, They shall be liable to credit the person with that amount.”