I created a product, and added pattern attributes, which had 3 values (flower, diamond, and heart). I had 3 images, one for each pattern value. 

So, I went to the product variant page, and selected one variant (flower), and upload flower pattern image, and saved it. 

Then I selected diamond variant, and when I went to image tab page, the flower pattern image was there too. So, I uploaded diamond image. did it the same for heart pattern. 

When switch to shop page, and select each attribute value, the image doesn't change at all. 

What do I need to do so each image is associated with the attribute value?