Unable to instantiate fragment net.gree.unitywebview.CWebViewPlugin

Hi,
We are using this plugin for both android and iOS. We got this below issue from Google Play Console after we upload it. Kindly provide us the solution ASAP.

Caused by android.app.Fragment$InstantiationException
Unable to instantiate fragment net.gree.unitywebview.CWebViewPlugin: calling Fragment constructor caused an exception
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android.app.Fragment.instantiate (Fragment.java:553)android.app.FragmentContainer.instantiate (FragmentContainer.java:53)android.app.FragmentState.instantiate (FragmentState.java:77)android.app.FragmentManagerImpl.restoreAllState (FragmentManager.java:2862)android.app.FragmentController.restoreAllState (FragmentController.java:140)android.app.Activity.onCreate (Activity.java:1113)com.unity3d.player.UnityPlayerActivity.onCreate (Unknown Source:4)com.google.firebase.MessagingUnityPlayerActivity.onCreate (MessagingUnityPlayerActivity.java:89)com.nextwave.unityandroidpermission.OverrideUnityPlayerActivity.onCreate (OverrideUnityPlayerActivity.java:39)android.app.Activity.performCreate (Activity.java:7376)android.app.Activity.performCreate (Activity.java:7367)android.app.Instrumentation.callActivityOnCreate (Instrumentation.java:1271)android.app.ActivityThread.performLaunchActivity (ActivityThread.java:3155)android.app.ActivityThread.handleLaunchActivity (ActivityThread.java:3312)android.app.servertransaction.LaunchActivityItem.execute (LaunchActivityItem.java:78)android.app.servertransaction.TransactionExecutor.executeCallbacks (TransactionExecutor.java:113)android.app.servertransaction.TransactionExecutor.execute (TransactionExecutor.java:71)android.app.ActivityThread$H.handleMessage (ActivityThread.java:2038)android.os.Handler.dispatchMessage (Handler.java:106)android.os.Looper.loop (Looper.java:226)android.app.ActivityThread.main (ActivityThread.java:7178)java.lang.reflect.Method.invoke (Method.java)com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:576)com.android.internal.os.ZygoteInit.main (ZygoteInit.java:942)

Start with the Android crash trace for net.gree.unitywebview.CWebViewPlugin and inspect how the fragment is instantiated during UnityPlayerActivity.onCreate. The issue does not name a source file, test, or complete underlying exception; done would require a reproducible cause and a verified Android fix.