How to commission a device to our fabric after adding it using Matter.Support We have the following configuration: eero border router our own thermostat device that we are developing no home pod or home TV are used We have followed this guide https://developer.apple.com/documentation/mattersupport/adding-matter-support-to-your-ecosystem and implemented Matter Extension, as Matter.Framework is no more allowed to pair device. In Matter Extension the following callbacks are fired: override func selectThreadNetwork(from threadScanResults: [MatterAddDeviceExtensionRequestHandler.ThreadScanResult]) async throws -> MatterAddDeviceExtensionRequestHandler.ThreadNetworkAssociation override func commissionDevice(in home: MatterAddDeviceRequest.Home?, onboardingPayload: String, commissioningID: UUID) async throws In our demo app the following function completes without errors try await request.perform() The thermostat device seems to be successfully commissioned. In https://developer.apple.com/documentation/mattersupport/adding-matter-support-to-your-ecosystem there is a comment that says: Use Matter.Framework APIs to pair the accessory to your application with the provided onboardingPayload. How should this thing be done ? We tried to start the matter controller in the old way: func start() -> Bool { if (self.matterController == nil) { let storage = MatterStorage.shared let factory = MTRDeviceControllerFactory.sharedInstance() let factoryParams = MTRDeviceControllerFactoryParams(storage: storage) do { try factory.start(factoryParams) } catch { return false } let keys = FabricKeys() let params = MTRDeviceControllerStartupParams(signing: keys, fabricId: UInt64(fabricId), ipk: keys.ipk) params.vendorID = NSNumber(value: self.vendorId) self.matterController = try? factory.createController(onExistingFabric: params) let controllerNid = self.matterController?.controllerNodeID if (self.matterController == nil) { self.matterController = try? factory.createController(onNewFabric: params) } } return (self.matterController != nil) } Certificate are generated locally as in Matter Darwin example. We tried to call let params = MTRCommissioningParameters() matterController?.commissionNode(withID: NSNumber(value: self.deviceNid), commissioningParams: params) in commissionDevice of Matter Extension but we get error: Invalid object state.