Can't unarchive worldMap(ARKit) from Firebase using NSKeyedUnarchiver.unarchivedObject

Question

I try to upload and unarchive World Map from firebase (which was previously serialized and loaded there), but I catch an error. Could you help me with my code. What am I doing wrong? Thank you.

@IBAction func downloadButtonAction(_ sender: Any) {
                
        //1. link on Firebase
        let storageRef = Storage.storage().reference(withPath: "folder/1.bmarwp")
        
        //2. Get data from firebase
        storageRef.getData(maxSize: 10 * 1024) { (data, error) in
            if let error = error {
                print("Got an error fetching data: \(error.localizedDescription)")
                return
            }
            
            if let data = data {
                //3. Unarchive object     
                //I GOT error here: value for key 'root' was of unexpected class 'NSDictionary'. Allowed classes are '{(ARWorldMap
                
                guard let downloadedMap = try! NSKeyedUnarchiver.unarchivedObject(ofClasses: [ARWorldMap.classForKeyedUnarchiver()], from: data) as? ARWorldMap
                else { fatalError("No ARWorldMap in archive.")}
                
                let configuration = ARWorldTrackingConfiguration()
                configuration.planeDetection = [.horizontal]
                
                if let downloadedMap = downloadedMap {
                    configuration.initialWorldMap = downloadedMap
                    self.showAlert(message: "Map loaded from server")
                } else {}
                
                let options: ARSession.RunOptions = [.resetTracking, .removeExistingAnchors]
                
                self.sceneView.debugOptions = [.showFeaturePoints]
                self.sceneView.session.run(configuration, options: options)
                
                return
            }
            
            
        }