CopyImg Function does not show image in front Prestashop

[lmejia]

Good afternoon I am trying to add images to my prestashop products.
The issue I have is that in the back the image looks good but when I enter the Front there the image does not appear. 
But if I click on the update button of the product at that moment the image starts to appear on the front.

 

I leave here below my code:

 

$image = new Image();
            $image->id_product = $product->id;
            $image->position = Image::getHighestPosition($product->id) + 1;
            $image->cover = true;
            $image->legend = substr($name,0,14);
            $image->add();

            $img = new MyAdminImportController();
            $img->copyImg($product->id, $image->id, $img_url, 'products', true);