public function refundSale($saleId, $refundAmount, $currency = CurrencyConst::EURO)
{
$apiContext = $this->connectionService->getApiContext();
$amount = new Amount();
$amount->setCurrency($currency)->setTotal($refundAmount);
$refund = new Refund();
$refund->setAmount($amount);
$sale = new Sale();
$sale->setId($saleId);
$refundSale = $sale->refund($refund, $apiContext);
return $refundSale;
}