Laravel route and optional params

I have some problems with my controller in laravel 5.4

My routes.php:

Route::group(array('domain' => '{subdomain}.site.com','as'=>'www::','middleware'=>array('web','varnish')), function() {

   Route::any('/material/{page?}/', [
      'as' => 'www_material', 'uses' => 'www\MaterialController@index'
   ]);

});

My controller:

<?php namespace App\Http\Controllers\www;

use App\Http\Controllers\Controller;
use View;
use DB;
use Illuminate\Http\Request;

class MaterialController extends Controller {

    public function index($subdomain, $page = 1, Request $request)
    {
        echo $subdomain;
        echo $page;
       //...some code
    }
}

There is no problems with url www.site.com/material/2/:

submodain = www,
page = 2

But www.site.com/material/:

Type error: Too few arguments to function App\Http\Controllers\www\MaterialController::index(), 2 passed and exactly 3 expected

I cant understand why this happend, because default value of page is 1.

Can someone help me? I cant solve this problem alone.

Thank you.

via Chebli Mohamed