Woocommerce: how to hide an option in the product page

Hi there,
I made a few variations on the webiste to allow the customers select the quantity.
I have set the 1 piece option too in variations to show in the page the single price but I would like to hide that option in the product page.

You can understand better following this link:

https://astuccieshoppers.com/ita/prodotto/collezione-10-02-articolo-m1-astuccio-con-shopper/

Can someone help? ty