(1) A payer is entitled to a refund from the payment service provider concerned of an authorised payment transaction which was initiated by or through a payee and which has already been executed, where both of the following conditions are satisfied:
(a) the authorisation did not specify the exact amount of the payment transaction when the authorisation was made;
(b) the amount of the payment transaction exceeded the amount the payer could reasonably have expected taking into account the previous spending pattern, the conditions in the framework contract concerned and any other relevant circumstances.
(2) At the payment service provider’s request, a payer shall bear the burden of proving the conditions referred to in paragraph (1) are satisfied.
(3) A refund under paragraph (1) shall be of the full amount of the executed payment transaction.
(4) The credit value date for the payment account of a payer refunded under paragraph (1) shall be no later than the date the amount was debited.
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