Error edit() must be an instance of App\User, none given

i created a UserController.php

use App\User;
//

class UsersController extends Controller
{
//

    public function edit($id, User $user){
      $user = $user->find($id);
      return view('admin.user.edit' , compact('user'));
    }

 //


}

And edit views

but when i want to access to this url

url('/users/'. $user->id .'edit')

i got this error

Error edit() must be an instance of App\User, none given

!?

via Chebli Mohamed