If you choose one of the options listed. The price changes. So when you press the add to cart button it's not sending the proper charge Try this link https://www.familyfriendlystore.com/products-detail.php?ProductID=1000&skucolor=4&skusize=7&skuudo1=15 the charge should be $0.04 but only $0.03 is being passed.
And if you choose this one https://www.familyfriendlystore.com/products-detail.php?ProductID=1000&skucolor=5&skusize=7&skuudo1=15 which should be $0.05 it's only sending $0.02.