rc-tree not showing navigation arrows(+,-) on react

Question

I have tried implementing simple rc-tree component in react, but it doesnt show "+" button which i can expand, it just shows the root parent names.

here is a sandbox link i have created https://codesandbox.io/s/flamboyant-stonebraker-ythlr?file=/src/App.js

sample code

<Tree
    defaultExpandAll={false}
    style={{ border: "1px solid #000" }}
    treeData={[
        {
            key: "0",
            title: "node 0",
            children: [
                {
                    key: "0-2",
                    title: "node 0-2",
                    children: [
                        { key: "0-2-0", title: "node 0-2-0" },
                        { key: "0-2-1", title: "node 0-2-1" }
                    ]
                },

                { key: "0-4", title: "node 0-4" }
            ]
        },
        {
            key: "1",
            title: "node 1",

            children: [
                {
                    key: "1-0",
                    title: "node 1-0",
                    children: []
                }
            ]
        }
    ]}
/>