/** * @param \Magento\Sales\Model\Quote\Payment $payment * @return \Magento\Sales\Model\Quote\Payment */ public function setPayment(\Magento\Sales\Model\Quote\Payment $payment) { if (!$this->getIsMultiPayment() && ($old = $this->getPayment())) { $payment->setId($old->getId()); } $this->addPayment($payment); return $payment; }