(1) The Commissioner shall not refund a revenue amount unless the person claiming the refund (in this section called the “claimant”)—
(a) satisfies the Commissioner that—
(i) he or she has not charged to, or recovered from, any other person an amount paid in respect of the whole or any part of the revenue amount; or
(ii) if the claimant has so charged or recovered any such amount—he or she has repaid the amount; and
(b) gives the Commissioner an undertaking in writing that he or she will not charge to, or recover from, any other person an amount paid in respect of the whole or any part of the revenue amount.
(2) If the Commissioner is not satisfied about the matters referred to in paragraph (1) (a) the Commissioner shall give the claimant notice in writing of his or her decision.
(3) A person who contravenes an undertaking that he or she has given under paragraph (1) (b) is liable to pay the Commissioner, as a penalty, an amount equal to double the amount that he or she has charged to, or recovered from, another person by the contravention.