Fatal error: Uncaught Error: Call to a member function authenticate() on null in /var/www/html/east/vendor/magento/module-product-alert/Controller/Add.php:43 Stack trace: #0 /var/www/html/east/vendor/magento/framework/Interception/Interceptor.php(58): Magento\ProductAlert\Controller\Add->dispatch() #1 /var/www/html/east/vendor/magento/framework/Interception/Interceptor.php(138): Snaptec\EmailStock\Controller\Add\Stock\Interceptor->___callParent() #2 /var/www/html/east/vendor/magento/framework/Interception/Interceptor.php(153): Snaptec\EmailStock\Controller\Add\Stock\Interceptor->Magento\Framework\Interception\{closure}() #3 /var/www/html/east/generated/code/Snaptec/EmailStock/Controller/Add/Stock/Interceptor.php(39): Snaptec\EmailStock\Controller\Add\Stock\Interceptor->___callPlugins() #4 /var/www/html/east/vendor/magento/framework/App/FrontController.php(186): Snaptec\EmailStock\Controller\Add\Stock\Interceptor->dispatch() #5 /var/www/html/east/vendor/magento/framework/App/FrontController.php(118): Magento\Framework\App\ in /var/www/html/east/vendor/magento/module-product-alert/Controller/Add.php on line 43