New field do not update in WP pannel

Hi,
I need to create in a woocommerce site a new field called “Codice Fiscale/P.IVA” in the following sections: 1) Registration form, 2) My account page; 3) User section in WP Pannel. I’ve created everything, but the new field has a iussue. It save only the user updates, bat if I change the informations and udate its by User section in WP Pannel, it do not save updates. Sorry for my english. This is the code I’ve inserted in function.php:
CODE
Can you help me?