You just pick a wrong binding for the image source. It must be selected from under the repeat in the data picker but you probably select it from under the API source.
Maybe check the detailed explanation here: Data Types and Binding and especially this screenshot:
https://community.wappler.io/uploads/default/original/2X/1/1e1be69d9f650cb13764d40b56e7ad719db545c7.png
It’s the same for any type of dynamic data/repeat with our tools.