Problems to export a element/object or see white color in Overprint fill

As the printscreens show. Object/Shape, if I put the colour white (standard), Neither in Overprint Fill and Neither in the Export. But if I clone the colour of this same object, from another element that I have in the Layout - That's it. That object was copied from another file, could it have been damaged the "codes" of that file. Because I don't find any effect, style, or any property, that can solve this question. I can't use the white from the file, but I can clone the colour of another object and that's it. Thank you for your attention Carlos Santos.