You added a pixel to the left, which is going to break your image, so get rid of that.
In usenti, instead of just hitting save, try to “save as” and select 16 colors without transparency, that should preserve the palette, though you will need to start with an image that has the palette intact.
GBAGE is a pretty outdated way of inserting graphics anyway, I recommend you take a look at buildfiles: https://tutorial.feuniverse.us/
Or at least febuilder: FE_Builder_GBA