App\Http\Controllers\Laralum\UsersController::deleteRel PHP Method

    public function deleteRel($user_id, $role_id)
    {
        Laralum::permissionToAccess('laralum.users.access');
        $rel = Role_User::whereUser_idAndRole_id($user_id, $role_id)->first();
        if ($rel) {
            $rel->delete();
        }
    }