diff --git a/android/build.gradle b/android/build.gradle
index 1afb315..e12da71 100644
--- a/android/build.gradle
+++ b/android/build.gradle
@@ -2,14 +2,14 @@ group 'com.kiwi.flutterscanbluetooth'
 version '1.0-SNAPSHOT'
 
 buildscript {
-    ext.kotlin_version = '1.3.41'
+    ext.kotlin_version = '1.7.20'
     repositories {
         google()
         mavenCentral()
     }
 
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.5.0'
+        classpath 'com.android.tools.build:gradle:7.3.1'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }
diff --git a/ios/Classes/SwiftFlutterScanBluetoothPlugin.swift b/ios/Classes/SwiftFlutterScanBluetoothPlugin.swift
index 34332ab..ad406b1 100644
--- a/ios/Classes/SwiftFlutterScanBluetoothPlugin.swift
+++ b/ios/Classes/SwiftFlutterScanBluetoothPlugin.swift
@@ -18,6 +18,8 @@ extension SwiftFlutterScanBluetoothPlugin: CBCentralManagerDelegate {
             print("central.state is .poweredOff")
         case .poweredOn:
             print("central.state is .poweredOn")
+        @unknown default:
+            break;
         }
     }
     
@@ -32,7 +34,7 @@ extension SwiftFlutterScanBluetoothPlugin: CBCentralManagerDelegate {
 }
 
 public class SwiftFlutterScanBluetoothPlugin: NSObject, FlutterPlugin {
-    var centralManager: CBCentralManager! = CBCentralManager(delegate: nil, queue: nil)
+    var centralManager: CBCentralManager?
     var bluetoothState: CBManagerState = .unknown
     let channel: FlutterMethodChannel
     var scanTimer: Timer?
@@ -40,7 +42,6 @@ public class SwiftFlutterScanBluetoothPlugin: NSObject, FlutterPlugin {
     init(_ channel: FlutterMethodChannel) {
         self.channel = channel
         super.init()
-        centralManager.delegate = self
     }
     
     public static func register(with registrar: FlutterPluginRegistrar) {
@@ -50,6 +51,11 @@ public class SwiftFlutterScanBluetoothPlugin: NSObject, FlutterPlugin {
     }
     
     public func handle(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
+        if(centralManager == nil){
+            centralManager = CBCentralManager(delegate: nil, queue: nil);
+        
+            centralManager?.delegate = self
+        }
         if(bluetoothState == .unsupported) {
             return result(FlutterError.init(code: "error_no_bt", message: nil, details: nil))
         }
@@ -59,12 +65,12 @@ public class SwiftFlutterScanBluetoothPlugin: NSObject, FlutterPlugin {
         
         switch call.method {
         case "action_start_scan":
-            if(centralManager.isScanning) {
+            if(centralManager?.isScanning ?? false) {
                 stopScan()
             }
-            centralManager.scanForPeripherals(withServices: nil, options: nil)
+            centralManager?.scanForPeripherals(withServices: nil, options: nil)
             
-            let bondedDevices = centralManager.retrieveConnectedPeripherals(withServices: [])
+            let bondedDevices = centralManager?.retrieveConnectedPeripherals(withServices: []) ?? []
             var res = [Dictionary<String, String>]()
             if(call.arguments as! Bool) {
                 for device in bondedDevices {
@@ -81,11 +87,15 @@ public class SwiftFlutterScanBluetoothPlugin: NSObject, FlutterPlugin {
         case "action_request_permissions":
             if(bluetoothState == .unauthorized) {
                 if #available(iOS 13.0, *) {
-                    switch centralManager.authorization {
+                    switch centralManager?.authorization {
                     case .denied, .restricted, .notDetermined:
                         return result(FlutterError.init(code: "error_no_permission", message: nil, details: nil))
                     case .allowedAlways:
                         break;
+                    case nil:
+                        break;
+                    case .some(_):
+                        break;
                     }
                 }
             }
@@ -98,7 +108,7 @@ public class SwiftFlutterScanBluetoothPlugin: NSObject, FlutterPlugin {
     
     func stopScan() {
         scanTimer?.invalidate()
-        centralManager.stopScan()
+        centralManager?.stopScan()
         channel.invokeMethod("action_scan_stopped", arguments: nil)
     }
 }
diff --git a/pubspec.yaml b/pubspec.yaml
index 0fbccfe..3dbc44e 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: flutter_scan_bluetooth
 description: Flutter plugin to scan Bluetooth devices.
-version: 2.1.4
+version: 2.1.5
 homepage: https://github.com/kiwi-bop/flutter_scan_bluetooth
 
 dependencies: