Then select just 2 edge vertices and move them down as well.
Switch to Top viewport again and select the 2 vertices of the opposite edge. Move them down so that they touch the perimeter of the NGon01.
Go to Modify panel and switch down to "NGon" in the Modifier stack. Expand the Rendering roll-out and set the values as Thickness = 0.7, Sides = 12, Check "Renderable" and Check "Display Render Mesh".
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