Zend certified PHP/Magento developer

System.log: main.CRITICAL: Warning: SimpleXMLElement::addChild(): unterminated entity reference

Hey I regularly get this error in my System.log. Can someone help me or say what’s the reason?

main.CRITICAL: Warning: SimpleXMLElement::addChild(): unterminated entity reference              EB in /var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Convert/ConvertArray.php on line 93 [{"function":"handler","class":"Magento\Framework\App\ErrorHandler","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Convert/ConvertArray.php","line":93,"function":"addChild","class":"SimpleXMLElement","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Convert/ConvertArray.php","line":100,"function":"_assocToXml","class":"Magento\Framework\Convert\ConvertArray","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Convert/ConvertArray.php","line":100,"function":"_assocToXml","class":"Magento\Framework\Convert\ConvertArray","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Convert/ConvertArray.php","line":47,"function":"_assocToXml","class":"Magento\Framework\Convert\ConvertArray","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/opengento/module-gdpr/Service/Export/Renderer/XmlRenderer.php","line":38,"function":"assocToXml","class":"Magento\Framework\Convert\ConvertArray","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/opengento/module-gdpr/Service/Export/Renderer/AbstractRenderer.php","line":37,"function":"render","class":"Opengento\Gdpr\Service\Export\Renderer\XmlRenderer","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/opengento/module-gdpr/Model/Export/ExportToFile.php","line":62,"function":"saveData","class":"Opengento\Gdpr\Service\Export\Renderer\AbstractRenderer","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/opengento/module-gdpr/Model/ExportEntityManagement.php","line":84,"function":"export","class":"Opengento\Gdpr\Model\Export\ExportToFile","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/opengento/module-gdpr/Cron/ExportEntity.php","line":59,"function":"export","class":"Opengento\Gdpr\Model\ExportEntityManagement","type":"->"},{"function":"execute","class":"Opengento\Gdpr\Cron\ExportEntity","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/module-cron/Observer/ProcessCronQueueObserver.php","line":368,"function":"call_user_func_array"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/module-cron/Observer/ProcessCronQueueObserver.php","line":879,"function":"_runJob","class":"Magento\Cron\Observer\ProcessCronQueueObserver","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/module-cron/Observer/ProcessCronQueueObserver.php","line":840,"function":"tryRunJob","class":"Magento\Cron\Observer\ProcessCronQueueObserver","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/module-cron/Observer/ProcessCronQueueObserver.php","line":280,"function":"processPendingJobs","class":"Magento\Cron\Observer\ProcessCronQueueObserver","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Event/Invoker/InvokerDefault.php","line":88,"function":"execute","class":"Magento\Cron\Observer\ProcessCronQueueObserver","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Event/Invoker/InvokerDefault.php","line":74,"function":"_callObserverMethod","class":"Magento\Framework\Event\Invoker\InvokerDefault","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Event/Manager.php","line":65,"function":"dispatch","class":"Magento\Framework\Event\Invoker\InvokerDefault","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/generated/code/Magento/Framework/Event/Manager/Proxy.php","line":95,"function":"dispatch","class":"Magento\Framework\Event\Manager","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/App/Cron.php","line":86,"function":"dispatch","class":"Magento\Framework\Event\Manager\Proxy","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/module-cron/Console/Command/CronCommand.php","line":126,"function":"launch","class":"Magento\Framework\App\Cron","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/symfony/console/Command/Command.php","line":298,"function":"execute","class":"Magento\Cron\Console\Command\CronCommand","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Interception/Interceptor.php","line":58,"function":"run","class":"Symfony\Component\Console\Command\Command","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Interception/Interceptor.php","line":138,"function":"___callParent","class":"Magento\Cron\Console\Command\CronCommand\Interceptor","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Interception/Interceptor.php","line":153,"function":"Magento\Framework\Interception\{closure}","class":"Magento\Cron\Console\Command\CronCommand\Interceptor","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/generated/code/Magento/Cron/Console/Command/CronCommand/Interceptor.php","line":23,"function":"___callPlugins","class":"Magento\Cron\Console\Command\CronCommand\Interceptor","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/symfony/console/Application.php","line":1040,"function":"run","class":"Magento\Cron\Console\Command\CronCommand\Interceptor","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/symfony/console/Application.php","line":301,"function":"doRunCommand","class":"Symfony\Component\Console\Application","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/magento/framework/Console/Cli.php","line":116,"function":"doRun","class":"Symfony\Component\Console\Application","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/vendor/symfony/console/Application.php","line":171,"function":"doRun","class":"Magento\Framework\Console\Cli","type":"->"},{"file":"/var/www/vhosts/magento2/httpdocs/bin/magento","line":23,"function":"run","class":"Symfony\Component\Console\Application","type":"->"}] []

Thanks for any help.