i got the answer in the Q&A section.
"Depth" property is used to determine the drawing order of the widgets within the same panel that use the same atlas. If you are using different atlases, bring the widgets forward on the transform's Z, moving them closer to the camera (-Z). If you are using different panels, adjust the transform of the panel you want to bring in front to a lower negative Z value (-Z). I highly recommend sticking to one atlas if you can manage it, it will make your life significantly easier.