UnityPlayerActivity onCreate problem

Hi, I am trying to extend UnityPlayerActivity with the help of docs.unity3d. I have a simple jar file with MainActivity class and also included the file classes.jar to the libs folder. My class file has following code.

 package com.example.testactivity;
 
 import android.os.Bundle;
 import android.util.Log;
 import android.view.Menu;
 import com.unity3d.player.UnityPlayerActivity;
 
 public class MainActivity extends UnityPlayerActivity 
 {
  
     @Override
     public void onCreate(Bundle savedInstanceState) {
         Log.i("Hiren","==============ON CREATE CALLED==============");
         super.onCreate(savedInstanceState);
         
        
     }
 
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.activity_main, menu);
         return true;
     }
     
     public static void callMe()
     {
         Log.i("Hiren","==============Function CALLED==============");
     }
 }

I can call the static function callMe () through my c# script but my onCreate() is not called at the start of the activity. My C# script is

 private static FBShare _instance;
     
     public static FBShare Instance
     {
         get
         {
             if(_instance == null) 
                 _instance = new FBShare();
             return _instance;
         }
     }
     
     private AndroidJavaClass cls_Fb = new AndroidJavaClass("com.example.testactivity.MainActivity");
     
     public void CallMe()
     {
         
         using(AndroidJavaClass cls_UnityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer")) 
         {
             
             using(AndroidJavaObject obj_Activity = cls_UnityPlayer.GetStatic<AndroidJavaObject>("currentActivity")) 
             {
                 cls_Fb.CallStatic("callMe");
             }
         }

When I call "CallMe" method, I get log of being called. but I didnt get any log from onCreate(). My AndroidManifest.xml is also fine I guess. It has activity of the class

 <activity android:name=".MainActivity"  
                   android:label="@string/app_name"
                   android:configChanges="keyboardHidden|orientation" >
               <meta-data android:name="android.app.lib_name" android:value="unity" />
                   <meta-data android:name="unityplayer.ForwardNativeEventsToDalvik" android:value="true" />
         </activity>

Is there any problem in my code?