Problem with the Custom Field Price Plugin

-- HikaShop version -- : 6.8.1 Bussines
-- Joomla version -- : 5.4.7
-- PHP version -- : 8.3.36
-- Browser(s) name and version -- : Chrome 157.0

Hello,
I am having an issue with the Custom Field Price plugin. When placing an order for a T-shirt, the price of 21.90 is displayed once the size and color are selected.
However, if a name print option (costing 1.79) is selected, this amount is not added to the total in the shopping cart. When editing the item within the cart, it becomes apparent that the selection for the name print was not saved. Although it is possible to set the option to "yes" there, the 1.79 is still not added to the price. The Custom Price plugin is enabled and configured.

I would appreciate your urgent assistance. Thank you in advance.