Effects like Element 3D process before transforms like scaling do, so Element sees a 3840x2160 solid and is trying to work in that.
If that's what's causing your problem, you can change the size of the solid by selecting it and pressing Ctrl+Shift+Y (PC) or Cmd+Shift+Y (Mac), or by using the Layer > Solid settings... menu item. You will also need to reset the layer's scale property to 100%.
Walter Soyka
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