Failed to handle method call

[Ckc1124]

my code:

version: 0.1.6

issue E/MethodChannel#flutter_background( 9919): Failed to handle method call E/MethodChannel#flutter_background( 9919): kotlin.KotlinNullPointerException E/MethodChannel#flutter_background( 9919): at de.julianassmann.flutter_background.FlutterBackgroundPlugin.onMethodCall(FlutterBackgroundPlugin.kt:67) E/MethodChannel#flutter_background( 9919): at io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage(MethodChannel.java:230) E/MethodChannel#flutter_background( 9919): at io.flutter.embedding.engine.dart.DartMessenger.handleMessageFromDart(DartMessenger.java:85) E/MethodChannel#flutter_background( 9919): at io.flutter.embedding.engine.FlutterJNI.handlePlatformMessage(FlutterJNI.java:692) E/MethodChannel#flutter_background( 9919): at android.os.MessageQueue.nativePollOnce(Native Method) E/MethodChannel#flutter_background( 9919): at android.os.MessageQueue.next(MessageQueue.java:335) E/MethodChannel#flutter_background( 9919): at android.os.Looper.loop(Looper.java:183) E/MethodChannel#flutter_background( 9919): at android.app.ActivityThread.main(ActivityThread.java:7697) E/MethodChannel#flutter_background( 9919): at java.lang.reflect.Method.invoke(Native Method) E/MethodChannel#flutter_background( 9919): at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592) E/MethodChannel#flutter_background( 9919): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:952) E/flutter ( 9919): [ERROR:flutter/lib/ui/ui_dart_state.cc(166)] Unhandled Exception: PlatformException(error, null, null) E/flutter ( 9919): #0 StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:572:7) E/flutter ( 9919): #1 MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:161:18) E/flutter ( 9919): E/flutter ( 9919): #2 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:334:12) E/flutter ( 9919): #3 FlutterBackground.hasPermissions (package:flutter_background/src/flutter_background.dart:37:27) E/flutter ( 9919): #4 _ModuleSelectMainPageState.build.. (package:FlutterApp/common/widget/module_select_main_page.dart:209:71) E/flutter ( 9919): #5 _InkResponseState._handleTap (package:flutter/src/material/ink_well.dart:992:19) E/flutter ( 9919): #6 _InkResponseState.build. (package:flutter/src/material/ink_well.dart:1098:38) E/flutter ( 9919): #7 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:184:24) E/flutter ( 9919): #8 TapGestureRecognizer.handleTapUp (package:flutter/src/gestures/tap.dart:524:11) E/flutter ( 9919): #9 BaseTapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:284:5) E/flutter ( 9919): #10 BaseTapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:219:7) E/flutter ( 9919): #11 PrimaryPointerGestureRecognizer.handleEvent (package:flutter/src/gestures/recognizer.dart:477:9) E/flutter ( 9919): #12 PointerRouter._dispatch (package:flutter/src/gestures/pointer_router.dart:78:12) E/flutter ( 9919): #13 PointerRouter._dispatchEventToRoutes. (package:flutter/src/gestures/pointer_router.dart:124:9) E/flutter ( 9919): #14 _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:377:8) E/flutter ( 9919): #15 PointerRouter._dispatchEventToRoutes (package:flutter/src/gestures/pointer_router.dart:122:18) E/flutter ( 9919): #16 PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:108:7) E/flutter ( 9919): #17 GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:220:19) E/flutter ( 9919): #18 GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:200:22) E/flutter ( 9919): #19 GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:158:7) E/flutter ( 9919): #20 GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:104:7) E/flutter ( 9919): #21 GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:88:7) E/flutter ( 9919): #22 _rootRunUnary (dart:async/zone.dart:1206:13) E/flutter ( 9919): #23 _CustomZone.runUnary (dart:async/zone.dart:1100:19) E/flutter ( 9919): #24 _CustomZone.runUnaryGuarded (dart:async/zone.dart:1005:7) E/flutter ( 9919): #25 _invoke1 (dart:ui/hooks.dart:267:10) E/flutter ( 9919): #26 _dispatchPointerDataPacket (dart:ui/hooks.dart:176:5) E/flutter ( 9919):