As noted in the previous reply, that is the intended behavior for this product template. It is a custom frame product, where you design on the outer frame and it comes with the center blank, for inserting a photo into in real life. The frame itself is printed, not the photo area in the center.
If you like, we can help you develop custom product templates to meet your specs. You can purchase that service here through our website for a one-time fee per template, and you can keep the IDs private to your site once they’re made. Our new-product-template creation services can be purchased here: https://www.mystyleplatform.com/product-category/customizable-products/
Also, if you want just blank templates of various sizes, you can do that yourself by using the plugin TM Extra Product Options by ThemeComplete and by setting up “width” and “height” fields. Then, enabling “configur8” within the ADvanced MyStyle product tab. This will allow the customize button to be clicked and then use the Address bar to copy a link to that size. Use that link within your design when you make buttons for that product, etc. When you do this, the URLs that go through and are recognized by MyStyle and load then at the sizes set on the product page when it goes through to the MyStyle Customizer on the next page.
It’s a bit complicated, I know, which is why we’d recommend our Standard License support so we can help you out with it, or just to purchase premade templates from us that will work right away with a single ID.