Metafields are empty

Hi, I need your help, please.. I need to edit two Custom Fields (meta fields) in Bulky “Edit Products” view…
I have created two Custom Fields that shows in my Front End products
1. One of them, calls “garantia” was created in “Advanced Custom Fields” plugin. This custom field, is a select field with several options.
2. Other Custom Field calls “marca” and was create from “Brands for WooCommerce” plugin. This Custom fields is a select field with several options too.
In Bulky “Edit Products” view, I get nothing in this two fields. For example in my product with ID 2942 called “Teclado mecánico Asus Tuf Gaming K3 RGB” the “garantia” field is “3 meses” and “marca” field is ASUS…
https://selling-tech.com/producto/teclado-mecanico-asus-tuf-gaming-k3-rgb/
Do you know why the plugin do not get any information in this two fields?
Thanks in advance.