featureless

When I use 'sonata_block_exists' in twig template I have this error: request.CRITICAL: Uncaught PHP Exception Symfony\Component\Debug\Exception\UndefinedMethodException: "Attempted to call an undefined method named "exists" of class "Symfony\Cmf\Bundle\BlockBundle\Block\PhpcrBlockLoader"." at C:\projets\vendor\sonata-project\block-bundle\Block\BlockLoaderChain.php line...