variant null value issue

-- HikaShop version -- : 4.7.0
-- Joomla version -- : 3.10.11
-- PHP version -- : 8.0.27
-- Browser(s) name and version -- : all
-- Error-message(debug-mod must be tuned on) -- : NONE is not an acceptable value

We allow a customer to choose 0, 1, 2 or 3 different custom embroideries on a number of products.

To do that we add an option which is another product with four variants. None - One - Two - Three

The problem which has just appeared after PHP and Hikashop updates is that the NONE value (a customer who wants no custom embroidery) now tosses up, briefly, an error message that NONE is not an acceptable value... or something like that.

I solved the problem by assigning a value to the NONE variant of 0.01 USD as that variant will not accept zero as a value.

This did not happen before.

What is the fix????

thanks