How to add a drag action effect to a specific object in the scene？

Hello everyone, I have just started learning the development and learning of visionPro app. I have a scene called Scene, and inside it is an object called Sphere. I want to add a drag animation to this Sphere alone. I follow the code below to achieve it. But my Sphere cannot actually be dragged in the Apple simulator. What is the reason?

struct ContentView: View {

    @State var enlarge = false
    @State var offset: Point3D = .zero
    @State var sphereEntity: Entity?
    
    var body: some View {
        RealityView { content in

            if let scene = try? await Entity(named: "Scene", in: realityKitContentBundle) {
                content.add(scene)
                sphereEntity = content.entities.first?.findEntity(named: "Sphere")
                sphereEntity?.components.set(InputTargetComponent(allowedInputTypes: .all))
            }

        }.gesture(DragGesture().targetedToEntity(sphereEntity ?? Entity()).onChanged({ value in
            print(value.location3D)
            sphereEntity?.position = value.convert(value.location3D, from: .local, to: sphereEntity?.parent! ?? Entity())
        }))
        .gesture(SpatialTapGesture().targetedToAnyEntity().onEnded({ _ in
            print("Ssssssss")
        })) .onAppear() {

        }
            
    }
}