I've encountered a very funny issue in a react-native app. I've got a project which is almost fully developed. Now the thing is, the android app crashes as soon as the internet is turned off which is not the case in iOS. This is what I got on Crashlytics for the crash -

```
Fatal Exception: com.facebook.react.common.JavascriptException: undefined is not a function (evaluating 'n({type:e.connectionType,effectiveType:e.effectiveConnectionType})'), stack:
<unknown>@287:358
value@32:1366
value@18:3177
<unknown>@18:911
value@18:2606
value@18:883

       at com.facebook.react.modules.core.ExceptionsManagerModule.showOrThrowError(ExceptionsManagerModule.java:56)
       at com.facebook.react.modules.core.ExceptionsManagerModule.reportFatalException(ExceptionsManagerModule.java:40)
       at java.lang.reflect.Method.invoke(Method.java)
       at java.lang.reflect.Method.invoke(Method.java:372)
       at com.facebook.react.bridge.JavaMethodWrapper.invoke(JavaMethodWrapper.java:374)
       at com.facebook.react.bridge.JavaModuleWrapper.invoke(JavaModuleWrapper.java:162)
       at com.facebook.react.bridge.queue.NativeRunnable.run(NativeRunnable.java)
       at android.os.Handler.handleCallback(Handler.java:739)
       at android.os.Handler.dispatchMessage(Handler.java:95)
       at com.facebook.react.bridge.queue.MessageQueueThreadHandler.dispatchMessage(MessageQueueThreadHandler.java:31)
       at android.os.Looper.loop(Looper.java:155)
       at com.facebook.react.bridge.queue.MessageQueueThreadImpl$3.run(MessageQueueThreadImpl.java:194)
       at java.lang.Thread.run(Thread.java:818)

```

While debugging, I get that red overlay on Android, so can anyone suggest on how to find the root cause of the crash. For starters, I can see that the project has used both 

```
NetInfo.isConnected.addEventListener(
            'connectionChange',
            this.connectivityChangeListener
        );

```

at some places and at some places

```
let isConnected = await NetInfo.isConnected.fetch();

```

to detect the network connection.