Fatal error: Uncaught Error: Call to a member function getChildrenCategories() on null in /home/shedsdev/public_html/app/code/Sixty/SubcategoryNavigation/Block/Submenu.php:60 Stack trace: #0 [internal function]: Sixty\SubcategoryNavigation\Block\Submenu->getCategories(NULL) #1 /home/shedsdev/public_html/vendor/magento/framework/View/TemplateEngine/Php.php(82): call_user_func_array(Array, Array) #2 /home/shedsdev/public_html/app/code/Sixty/SubcategoryNavigation/view/frontend/templates/sidebar.phtml(4): Magento\Framework\View\TemplateEngine\Php->__call('getCategories', Array) #3 /home/shedsdev/public_html/vendor/magento/framework/View/TemplateEngine/Php.php(59): include('/home/shedsdev/...') #4 /home/shedsdev/public_html/vendor/magento/framework/Interception/Interceptor.php(58): Magento\Framework\View\TemplateEngine\Php->render(Object(Sixty\SubcategoryNavigation\Block\Submenu\Interceptor), '/home/shedsdev/...', Array) #5 /home/shedsdev/public_html/vendor/magento/framework/Interception/Interceptor.php(138): Magento\Framework in /home/shedsdev/public_html/app/code/Sixty/SubcategoryNavigation/Block/Submenu.php on line 60