I am working in VOIP application. I can receive voip push when app in background or foreground. But when an app is killed and device locked voip delegate **"didReceiveIncomingPushWithPayload"** method not called. 

Also, I am facing below crash

**Killing VoIP app  because it failed to post an incoming call in time**

**VoIP push for app  dropped on the floor**


**Appdelegate didFinishLaunching**
```
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    NSLog(@"didFinishLaunchingWithOptions");
    // register remote notification
    [CCFMessageControl sharedInstance].calldelegate = [CallBackManager sharedInstance];
    [CallBackManager sharedInstance].callPayloadDict = [[NSMutableArray alloc] init];
    store = [[CNContactStore alloc] init];
    [self registerForRemoteNotification];
    if (application.applicationState == UIApplicationStateInactive) {
        if (![UserDefaultCoreDBManager isRealmFileExist]) {
            [self presentTouchID];
        }
    }
    // Initialize Core Data Password
    [CoreDataSecurity storeDBEncryptionKeyInKeychain];
    [CoreDBManager initialiseCoreData];
    [CCFSharedMethod setUserDefaultBool:NO withKey:kMigrationInprogress];
    
    
    //Check Realm Migration
    if ([UserDefaultCoreDBManager isRealmFileExist]) {
         // Realm DB initialize
        // to disable file protection on accessing realm file when device is locked
        
        [self setDefaultRealmPath];
        [NotificationsCommonHandler migrationForRealm];
        [self clearLocks];
        // print Realm file path
        NSLog(@"filepath - %@",[[RLMRealmConfiguration defaultConfiguration] fileURL]);
     }
    //
    if (launchOptions[UIApplicationLaunchOptionsShortcutItemKey]) {
        UIApplicationShortcutItem *shortcutItem = launchOptions[UIApplicationLaunchOptionsShortcutItemKey];
        self.launchedShortcutItem = shortcutItem;
    }
    // Check and Update Resource IP
//    [CCFLoginHelper getResourceIPAddressAndUpdate];
    // Use Firebase library to configure APIs
    // Use crashlytics to trace crashes
    [FIRApp configure];
    NSString *bundleIdentifier = [[NSBundle mainBundle] bundleIdentifier];
    [FIROptions defaultOptions].deepLinkURLScheme = bundleIdentifier;
    //    // Firebase Force Update
    [CCFRemoteConfig.sharedManager Configure];
    // To remove the notifications in Notification Center:
    [[UNUserNotificationCenter currentNotificationCenter] removeAllDeliveredNotifications];
    [[UNUserNotificationCenter currentNotificationCenter] removeAllPendingNotificationRequests];
    // To set the badge (0 is no badge at all):
    [[UIApplication sharedApplication] setApplicationIconBadgeNumber:0];

    if([UINavigationBar conformsToProtocol:@protocol(UIAppearanceContainer)]) {
        [UINavigationBar appearance].tintColor = [UIColor whiteColor];
    }
    // set navigation bar background color
    [[UINavigationBar appearance] setBarTintColor: NEW_THEME_WHITE];

    // navigation title color and font
    [[UINavigationBar appearance] setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys:[UIColor blackColor], NSForegroundColorAttributeName, FontRoboto, NSFontAttributeName, nil]];
    [[NSUserDefaults standardUserDefaults] setValue:APP_NAME forKey:@"appName"];

    [[UITabBar appearance] setTintColor:NEW_THEME_COLOR];
    // Google Sign In

    // //   [CoreDBManager stopAllOnProgressMedia];

    //Checking Coredata migation
    if ([UserDefaultCoreDBManager isRealmFileExist]){
        //  //  Check coredata migration
        CoreDataMigrationVC *coreDataMigrationVC = [[CoreDataMigrationVC alloc] initWithNibName:@"CoreDataMigrationVC" bundle:nil];
        UIViewController *windowController = [[UINavigationController alloc]initWithRootViewController:coreDataMigrationVC];
        self.window.rootViewController = windowController;
        self.window.backgroundColor=[UIColor whiteColor];
        [self.window makeKeyAndVisible];
    }else{
        [self setUserBasedRootViewController];
    }

    
    if (launchOptions[UIApplicationLaunchOptionsShortcutItemKey]) {
        UIApplicationShortcutItem *shortcutItem = launchOptions[UIApplicationLaunchOptionsShortcutItemKey];
        self.launchedShortcutItem = shortcutItem;
    }
    if(![CCFSharedMethod getUserDefaultBoolForKey:@"firstLaunch"]){
        [CCFSharedMethod setUserDefaultBool:YES withKey:@"firstLaunch"];
        @try {
            NSData *imageData = [NSKeyedArchiver archivedDataWithRootObject:[UIImage imageNamed:@"chat bg"] requiringSecureCoding:NO error:nil];
            [[NSUserDefaults standardUserDefaults] setObject:imageData forKey:@"wallpaperImage"];
        } @catch (NSException *exception) {
            NSLog(@"Error  = %@", exception.reason);
        } @finally {
            NSLog(@"finally");
        }
        
        [CCFSharedMethod setUserDefaultBool:NO withKey:@"isSolidColor"];
    }

    if ([[NSUserDefaults standardUserDefaults]valueForKey:KProfileBackgroundColor] == nil) {
        [[NSUserDefaults standardUserDefaults] setObject:[CCFCommonClass getrandomPlaceHolderColor] forKey:KProfileBackgroundColor];
    }
    // IP Address Change Notifier
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(updateIpAddressOnNetworkChange) name:kReachabilityChangedNotification object:nil];
    // Auto Download Settings
    if (![CCFCommonClass sharedInstance].chatSettingsArray.count) {
        [[CCFCommonClass sharedInstance] composeChatSettingsArray];
    }
    // Exclude from backup
//    [self setupExcludeFromBackup];
    return YES;
}
```

**Resigter voip Notification**


``` 
- (void)registerVOIPNotifications {
    dispatch_queue_t mainQueue = dispatch_get_main_queue();
    PKPushRegistry *pushRegistry = [[PKPushRegistry alloc] initWithQueue:mainQueue];
    pushRegistry.delegate = self;
    pushRegistry.desiredPushTypes = [NSSet setWithObject:PKPushTypeVoIP];
}
```

**didReceiveIncomingPushWithPayload delegate method**

```
- (void)pushRegistry:(PKPushRegistry *)registry didReceiveIncomingPushWithPayload:(PKPushPayload *)payload forType:(PKPushType)type withCompletionHandler:(void (^)(void))completion {
    NSLog(@"Push VOIP Received with Payload - %@",payload.dictionaryPayload);
    [VOIPManager.sharedInstance processPayload:payload.dictionaryPayload completion:^{
        completion();
    }];
}
```

**Process payload**
```
- (void)processPayload:(NSDictionary *)userInfo completion:(void (^)(void))callback {
    if (![CCFSharedMethod getUserDefaultBoolForKey:klLogin] || ![CCFSharedMethod ownJID].length) {
        NSLog(@"Push Status VOIP Not Logged IN");
        return;
    }
    NSString *messageType = [userInfo valueForKey:@"type"];
    
    /* ***** Call Processing ***** */
    
    if ([messageType isEqualToString:kCallElement]) {
        
        CallModel *callModel = [[CallModel alloc]initWithDictionary:userInfo];
        NSLog(@"Push Status VOIP Call MESSAGE RECEIVED");
        
        if (@available(iOS 13.0, *))  {
            [self handleCallForiOS13ForCallModel:callModel completion:^{
                callback();
            }];
        } else {
            [self handleCallForBelowiOSForCallModel:callModel];
        }
    }else {
        // handle message received as VOIP notification
        [self handleMessageWithPayload:userInfo];
    }
}
```

**handleCallForiOS13ForCallModel**

```
- (void)handleCallForiOS13ForCallModel:(CallModel *)callModel completion:(void (^)(void))callback {
    {
        // If version is 13.0 or above
        NSLog(@"STEP CALL MESSAGE RECEIVED");
        
        /* ***** Processing Call ***** */
        if(!CallKitManager.sharedInstance.callUUID) {
            // New Call
            NSLog(@"Push Status VOIP Reporting call to CallKit");
            CallKitManager.sharedInstance.delegate = CallBackManager.sharedInstance;
            [CallKitManager.sharedInstance reportIncomingCallWithPhoneNumber:callModel.callerName.length > 0 ? callModel.callerName : @"Unknown" hasVideo:[callModel.callType isEqualToString:klVideoCall] completion:^{
                callback();
            }];
        }else {
            NSLog(@"Push Status VOIP already on MF call. So no need to inform CallKit. End / Engaged to this Caller - %@",callModel.socketID);
        }
        if([callModel.callStatus isEqualToString:kEndedStatus] && (![CallBackManager.sharedInstance.callID isEqualToString:callModel.callID] || !CallBackManager.sharedInstance.ownSocketId)) {
            NSLog(@"Push Status VOIP Call Invalid END Staus - %@",callModel.socketID);
        }else {
            NSLog(@"Push Status VOIP Call Inform to Callback Manager - %@",callModel.socketID);
            [CallBackManager.sharedInstance didReceiveIOS13VOIPCallMessageWithCallModel:callModel];
            
            if ([callModel.callStatus isEqualToString:kEndedStatus]) {
                NSLog(@"Push Status VOIP Call CALL DEALLOC & ENDED for %@",callModel.socketID);
            }else {
                currentCall = callModel;
            }
        }
        /* ***** Remove Invalid message from notification bar ***** */
        [NotificationsCommonHandler removeInvalidMessageForIDs:@[CCFInvalidMessageID,callModel.callID] onCompletion:nil];
        
    }
}
```

**Report Incoming Call**
```
- (void)reportIncomingCallWithPhoneNumber:(NSString *)phoneNumber hasVideo:(BOOL)hasVideo completion:(void (^)(void))callback {
    [self configureAudioSessionFortheCall];
    
    self.update = [[CXCallUpdate alloc] init];
    self.update.supportsHolding = YES;
    self.update.hasVideo = hasVideo;
    self.update.remoteHandle = [[CXHandle alloc] initWithType:CXHandleTypeGeneric value:phoneNumber];
    if (self.callUUID == nil) {
        self.callUUID = [NSUUID new];
    }
    _customCallModel->isCallConnected = NO;
    _customCallModel->isOutgoingCall = NO;
    [NotificationsCommonHandler saveCallKitCallInUserDefaults:_customCallModel];
    NSLog(@"STEP CALLKIT REPORTING INCOMING CALL WITH SOCKETID %@",CallBackManager.sharedInstance.peerSocketId);
    [self.provider reportNewIncomingCallWithUUID:self.callUUID update:self.update completion:^(NSError * _Nullable error) {
        if (!error) {
            NSLog(@"STEP CALLKIT UI DISPLAYED FOR SOCKETID %@",CallBackManager.sharedInstance.peerSocketId);
           
        } else {
            if (self.delegate && [self.delegate respondsToSelector:@selector(callDidFailed)]) {
                [self.delegate callDidFailed];
            }
        }
        callback();
    }];
}
```