I'd like to second this suggestion! This is a clear bug in the mod that is not working as intended. I understand not wanting to add additional fixes and risk messing up the modpack balance with the official update that fixed this, but it seems like the admin shop is a clear, easy work around to deal with this bug. Given that the original poster holds the monopoly on the product currently and is asking for the fix, fixing this problem with the admin shop wouldn't destabalize the economy. Please provide a workaround for this error in the code.