code: protected function validateDeliveryAddressOptIn()
      {
          $return = true;
          $optin = (int) $this->getRequestParameter('oegdproptin_deliveryaddress');
          $changeExistigAddress = (int) $this->getRequestParameter('oegdproptin_changeDelAddress');
          $addressId = $this->getRequestParameter('oxaddressid');
          $deliveryAddressData = $this->_getDelAddressData();
  
          if (\OxidEsales\Eshop\Core\Registry::getConfig()->getConfigParam('blOeGdprOptinDeliveryAddress')
              && ((null == $addressId) || ('-1' == $addressId) || (1 == $changeExistigAddress))
              && !empty($deliveryAddressData)
              && (1 !== $optin)
              ) {
              $return = false;
          }
          return $return;
      }
docs: Validate delivery address optin.
  Needed if we get delivery address data from request.
  
  @return bool