[scenekit/ARkit] How to put Node with name, then change position later

How to put SCNNode with name, then change position later, is below

let planeGeometry = SCNBox(width: 1,
                               height: 0.01,
                               length: 1,
                               chamferRadius: 0)
let planeNode = SCNNode(geometry: planeGeometry)
node.name = "plane"

let node = scene.rootNode.childNode(withName: "plane", recursively: true)
node.position  = SCNVector3Make(x,y,z)