objectManager = \Magento\Framework\App\ObjectManager::getInstance(); } public function getCustomerByEmail($email) { $websiteID = $this->storeManage->getStore()->getWebsiteId(); $customer = $this->customer->create()->setWebsiteId($websiteID)->loadByEmail($email); return $customer; } public function register($email) { $subscriber= $this->objectManager->create('Magento\Newsletter\Model\SubscriberFactory'); $subscriber->create()->subscribe($email); } }