Redirect with flash data in laravel 5 does not work

When I submit a form I want to redirect back to the current view/blade with some data:

here is my redirect:

return redirect('configbeacon')->with('requirement', 'req');

here is my blade where I check if 'requirement' is set:

@if(Session::has('requirement'))
            <div class="alert alert-success" role="alert">
                <span class="sr-only">Error:</span>
                Dit tilbud blev gemt
                <span class="glyphicon glyphicon-ok" aria-hidden="true"></span>
            </div>
        @endif

But it does not show the elements inside the if loop... Thank you.

via Chebli Mohamed