send the form is not possible

Hi everyone,When i fill in the form online, he can not find the page (404)I can not figure out why not.Im using latest joomla and the latest easybook reloaded pro.Hope someone can help me out.. 
Here my call stack: Er heeft zich een fout voorgedaan.
De opgevraagde pagina kan niet worden gevonden.Ga op de website zoeken of ga naar de startpagina. Startpagina 404Er heeft zich een fout voorgedaan.
Als de problemen blijven bestaan, neem dan aub contact op met de beheerder van de website en rapporteer onderstaande fout..Call stack#FunctionLocation1()JROOT/components/com_easybookreloaded/src/Model/EntryModel.php:1942KubikRubik\Component\EasybookReloaded\Site\Model\EntryModel->store()JROOT/components/com_easybookreloaded/src/Controller/EntryController.php:1283KubikRubik\Component\EasybookReloaded\Site\Controller\EntryController->save()JROOT/libraries/src/MVC/Controller/BaseController.php:6784Joomla\CMS\MVC\Controller\BaseController->execute()JROOT/libraries/src/Dispatcher/ComponentDispatcher.php:1435Joomla\CMS\Dispatcher\ComponentDispatcher->dispatch()JROOT/libraries/src/Component/ComponentHelper.php:3616Joomla\CMS\Component\ComponentHelper::renderComponent()JROOT/libraries/src/Application/SiteApplication.php:2087Joomla\CMS\Application\SiteApplication->dispatch()JROOT/libraries/src/Application/SiteApplication.php:2498Joomla\CMS\Application\SiteApplication->doExecute()JROOT/libraries/src/Application/CMSApplication.php:2939Joomla\CMS\Application\CMSApplication->execute()JROOT/includes/app.php:6110require_once()JROOT/index.php:32

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