I have a problem with product preview and I am not able to solve it by myself 🙁
When you check my store, you can see first products are shown well, but “PREMADE LOGO DESIGN” products are squeezed. The frame size is perfect, but it didn’t crop the image, it squeezed it into that size. I will attach screen shots what I mean.
You can delete Product Images Width/Height and Product Thumbnails Width/Height in Theme Option, then go to Woocommerce > Settings > Products > Display and change settings. Use hard crop if you want to crop images. Then regenerate thumbnails https://wordpress.org/plugins/regenerate-thumbnails/