HTTP/1.1 422 Unprocessable Entity JSON render problem

Hi all, I'm developing a REST API using Transformers and JSON responses. I want to render proper error messages as jsonapi.org recommended.

My app/Exceptions/Handler.php render() method:

    public function render($request, Exception $e)
    {
        if ($e instanceof ModelNotFoundException) {
            $e = new NotFoundHttpException($e->getMessage(), $e);
        }

        $status = 500;
        $title  = 'General error';
        $detail = 'Sorry, something unthinkable happened now';

        switch($e){
            case ($e instanceof NotFoundHttpException):
                $status = 404;
                $title = 'The requested resource has not been found';
                $detail = '';
                break;
            case ($e instanceof MethodNotAllowedHttpException):
                $status = 405;
                $title = "Method not allowed exception";
                $detail = "The HTTP method '{$request->getMethod()}' is not allowed here";
                break;
            case ($e instanceof UnprocessableEntityHttpException):
                $status = 422;
                $title = "Unprocessable Entity";
                $detail = "We're sorry, we can not process your data what you've just sent to us";
                break;
        }

        return response()->json([
            'errors' => [
                [
                    'status'    => $status,
                    'source'    => ['pointer' => $request->getUri()],
                    'title'     => $title,
                    'detail'    => get_class($e)
                ]
            ]
        ], $status);
        
        return parent::render($request, $e);
    }

The NotFoundHttpException returns proper error as expected:

{
  "errors": [
    {
      "status": 405,
      "source": {
        "pointer": "http:\/\/localhost:8001\/api\/v1\/df\/documents"
      },
      "title": "Method not allowed exception",
      "detail": "Symfony\\Component\\HttpKernel\\Exception\\MethodNotAllowedHttpException"
    }
  ]
}

The problem is I can not catch validation errors like UnprocessableEntityHttpException, I get this back:

{
  "data.type": [
    "The data.type field is required."
  ]
}

How can I handle/transform all my exceptions to a proper JSON response?