How do I convert a custom menu wp_get_nav_menu_items into Fourth level?

how can I turn this function from Two-level into the Fourth level in WordPress? This function can only echo the parent and its child, but I'm trying to make it unlimited or at least 4 levels if it is possible

A
B -2
C -2 
    -3 -- Not Work
     -4 -- Not Work
D -2
F

this is my code: it works only till level 2

function wp_get_menu_array($current_menu) {
    $array_menu = wp_get_nav_menu_items($current_menu);
    $menu = array();
    foreach ($array_menu as $m) {
        if (empty($m-menu_item_parent)) {
            $menu[$m-ID] = array();
            $menu[$m-ID]['ID']          =   $m-ID;
            $menu[$m-ID]['title']       =   $m-title;
            $menu[$m-ID]['url']         =   $m-url;
            $menu[$m-ID]['children']    =   array();
        }
    }
    $submenu = array();
    foreach ($array_menu as $m) {
        if ($m-menu_item_parent) {
            $submenu[$m-ID] = array();
            $submenu[$m-ID]['ID']       =   $m-ID;
            $submenu[$m-ID]['title']    =   $m-title;
            $submenu[$m-ID]['url']      =   $m-url;
            $menu[$m-menu_item_parent]['children'][$m-ID] = $submenu[$m-ID];
        }
    }
    return $menu;
}


$menu_items = wp_get_menu_array('main-menu'); // Then call in your theme

  nav
      ul
        ?php foreach ($menu_items as $item) : ?
          li
            a href=?= $item['url'] ? title=?= $item['title'] ??= $item['title'] ?/a
            ?php if( !empty($item['children']) ):?
            ul class=sub-menu
              ?php foreach($item['children'] as $child): ?
                li class=b-main-header__sub-menu__nav-item
                  a href=?= $child['url'] ? title=?= $child['title'] ??= $child['title'] ?/a
                /li
              ?php endforeach; ?
            /ul
            ?php endif; ?
          /li
        ?php endforeach; ?
     ul
/nav