public function getContactsToImportByWebsite($websiteId, $syncLimit, $onlySubscriber = false)
    {
        $collection = $this->addFieldToSelect('*')
            ->addFieldToFilter('customer_id', ['neq' => '0'])
            ->addFieldToFilter('email_imported', ['null' => true])
            ->addFieldToFilter('website_id', $websiteId)
            ->setPageSize($syncLimit);

        if ($onlySubscriber) {
            $collection->addFieldToFilter('is_subscriber', 1)
                ->addFieldToFilter(
                    'subscriber_status',
                    \Magento\Newsletter\Model\Subscriber::STATUS_SUBSCRIBED
                );
        }

        return $collection;
    }