Image not changing in single product view

Hello, I installed your plugin but have an issue.

I have a product that has 2 attributes: 16 colors and 3 sizes. The price changes when different size is chosen but when a color is changed it should display image of the attribute chosen. It works on product list view but not on a single product view. Is this achievable? I do not want to add variations for each color x each size, that seems like a complicated thing to do.

I tried swithching to WP default theme and it works but when I activate my Blocksy theme it does not work. I tried disabling some options but still it does not work.