How to provide Laravel session persistence, when pushing data?

I have a form and it send requests to the Laravel. Laravel controller catch requests and store data in session by push method, for example

$basename = pathinfo($path, PATHINFO_BASENAME);

if (!$request->session()->exists('upload')) {

    $request->session()->put('upload', []);
}

$request->session()->push('upload', $basename);

var_dump($request->session()->get('upload'));

When form send two (or more) requests to Laravel, I expects to see in var_dump two (or more) values in array, but I see only one value. Why it can happening?

Thanks in advance!

via Chebli Mohamed