Error

exception 'RuntimeException' with message 'Error decoding JSON data: Syntax error' in /opt/apache_bitnami/apache2/htdocs/castellar/libraries/vendor/joomla/registry/src/Format/Json.php:72 Stack trace: #0 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/vendor/joomla/registry/src/Registry.php(366): Joomla\Registry\Format\Json->stringToObject('{"robots":"","a...', Array) #1 /opt/apache_bitnami/apache2/htdocs/castellar/components/com_content/models/article.php(180): Joomla\Registry\Registry->loadString('{"robots":"","a...') #2 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/legacy/view/legacy.php(408): ContentModelArticle->getItem() #3 /opt/apache_bitnami/apache2/htdocs/castellar/components/com_content/views/article/view.html.php(42): JViewLegacy->get('Item') #4 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/legacy/controller/legacy.php(664): ContentViewArticle->display() #5 /opt/apache_bitnami/apache2/htdocs/castellar/components/com_content/controller.php(113): JControllerLegacy->display(true, Array) #6 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/legacy/controller/legacy.php(702): ContentController->display() #7 /opt/apache_bitnami/apache2/htdocs/castellar/components/com_content/content.php(38): JControllerLegacy->execute(NULL) #8 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/cms/component/helper.php(405): require_once('/opt/apache_bit...') #9 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/cms/component/helper.php(380): JComponentHelper::executeComponent('/opt/apache_bit...') #10 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/cms/application/site.php(191): JComponentHelper::renderComponent('com_content') #11 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/cms/application/site.php(230): JApplicationSite->dispatch() #12 /opt/apache_bitnami/apache2/htdocs/castellar/libraries/cms/application/cms.php(261): JApplicationSite->doExecute() #13 /opt/apache_bitnami/apache2/htdocs/castellar/index.php(52): JApplicationCms->execute() #14 {main}