Problem with CUIHelper (C#)

Code:

            var elements = new CuiElementContainer();
            var mainName = elements.Add(new CuiPanel
            {
                Image =
                {
                    Color = "0.1 0.1 0.1 0.7"
                },
                RectTransform =
                {
                    AnchorMin = "0.01 0.00",
                    AnchorMax = "0.20 0.10"
                }
            },"Overlay", "StatsUI");            elements.Add(new CuiPanel
            {
                Image =
                {
                    Color = "0.5 0.5 0.5 0.3"
                },
                RectTransform =
                {
                    AnchorMin = "0.20 0.72",
                    AnchorMax = "0.85 0.90"
                }
            }, "StatsUI", "WCProgress");            elements.Add(new CuiPanel
            {
                Image =
                {
                    Color = "0.5 1.0 0.5 1.0"
                },
                RectTransform =
                {
                    AnchorMin = "0.05 0.05",
                    AnchorMax = "0.95 0.95"
                }
            }, "WCProgress", "WCProgressBar");

Why i can't see last element? i mean it supposed to be like this:
Overlay has -> StatsUI has -> WCProgress has ->WCProgressBar
But i can't see "WCProgressBar" why is that?