Hidden input doesn’t update

I’m using PPOM latest version and I have created array that should update pizza addons.

I don’t understand why it doesn’t work, following debugging, I have updated hidden input before submitting the form.

For example:

$( ".single_add_to_cart_button" ).click(function() { //On adding to cart
        $hidden = $(".print"); //Hidden input class
        $hidden.val('testing');
        console.log($hidden.val()); //Returns testing as expected
    });

After debugging returns ‘testing’, I’m watching the PPOM value field on the cart and it’s default value I defined.

How can I submit that correctly?

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