API Error REST Slim

  

Slim Application Error Type:   Doctrine \ DBAL \ Exception \ InvalidFieldNameException

I have a REST API configured with Slim and Doctrine and I need to resolve this error. The error appears when I make an HTTP request from my routes.php file:

  $app->get('/articulos{id}', function (Request $request, Response $response, array $args) {

      $em = getEntityManager();  
      $articulos = $em->getRepository('Articles')->findById($args['id']); 

  });

The structure of the project is as follows: Project

The HTTP request I make is a get(id) .

Does anyone know the solution?