wp_cache_get not updating

Hello

I’m the developer of QuadMenu

I have some users that have reported some issues when your plugin is activated

This function is cached but is not updating

Can you point me in some direction to fix the issue?

if (!$data = wp_cache_get('quadmenu', 'wp_get_nav_menu_items')) {

            $data = wp_get_nav_menu_items($menu_id);

            wp_cache_add('quadmenu', $data, 'wp_get_nav_menu_items');
        }

The page I need help with: [log in to see the link]