Product blocks have 2 options for items with multiple images, here's why and how to change it.
Image Gallery Type Setting
Within the 'Customizer' select the 'Product Page' from the drop down menu.
Next Click the Cog on the top right of the Product Block to open the Product Block 'Config' to show the various options available.
Then select whether you would like a Carousel or Standard Gallery type for product page images.
Carousel
If you select the carousel option then the product page image will have some arrows on the image for customers to scroll through the additional images available.
Customers can also click on the image to open it in a Lightbox that will fill the screen for a closer look, if they need it.
Standard
If you select Standard as the Gallery type then the customer will need to click the additional images. This will then open the relevant picture in a Lightbox that fills the screen and dims the background.