Implementing Admob in signed apk

i am trying to implement admob in my signed apk but it isn’t working. I am new to the use of plugins.these are all the changes i made.do i need to do something else?? heres my scripts and manifest:
advetisement handler:

using UnityEngine;
using System.Collections;

public class AdvertisementHandler : MonoBehaviour
{
    public enum AdvSize
    {
        BANNER,
        IAB_MRECT,
        IAB_BANNER,
        IAB_LEADERBOARD,
        SMART_BANNER,
        DEVICE_WILL_DECIDE
    };

    public enum AdvOrientation
    {
        VERTICAL,
        HORIZONTAL
    };

    public enum Position
    {
        NO_GRAVITY = 0,
        CENTER_HORIZONTAL = 1,
        LEFT = 3,
        RIGHT = 5,
        FILL_HORIZONTAL = 7,
        CENTER_VERTICAL = 16,
        CENTER = 17,
        TOP = 48,
        BOTTOM = 80,
        FILL_VERTICAL = 112
    };

    public enum AnimationInType
    {
        SLIDE_IN_LEFT, 
        FADE_IN,
        NO_ANIMATION
    };

    public enum AnimationOutType
    {
        SLIDE_OUT_RIGHT,
        FADE_OUT,
        NO_ANIMATION
    };

    public enum Activity
    {
        INSTANTIATE,
        DISABLE,
        ENABLE,
        HIDE,
        SHOW,
        REPOSITION
    }
    public enum LevelOfDebug
    {
        NONE,
        LOW,
        HIGH,
        FLOOD
    }

    static AndroidJavaClass admobPluginClass;
    static AndroidJavaClass unityPlayer;
    static AndroidJavaObject currActivity;

    /// <summary>
    /// Initializing Plugin with values
    /// </summary>
    /// <param name="pubID">Admob App ID</param>
    /// <param name="advSize">Advertisement Size</param>
    /// <param name="advOrient">Advertisement Orientation</param>
    /// <param name="position_1">Advertisement First Position</param>
    /// <param name="position_2">Advertisement Second Position</param>
    /// <param name="isTesting">Flag for testing game/app</param>
    /// <param name="testDeviceId">Test Device Id</param>
    /// <param name="animIn">Animation IN Type</param>
    /// <param name="animOut">Animation OUT Type</param>
    /// <param name="levelOfDebug">Debug Level</param>
    public static void Instantiate(string pubID, AdvSize advSize, AdvOrientation advOrient, Position position_1, Position position_2, bool isTesting, string testDeviceId, AnimationInType animIn, AnimationOutType animOut, LevelOfDebug levelOfDebug)
    {
        Debug.Log("Instantiate Called");
        admobPluginClass = new AndroidJavaClass("com.microeyes.admob.AdmobActivity");
        unityPlayer = new AndroidJavaClass("com.unity3d.player.UnityPlayer");
        currActivity = unityPlayer.GetStatic<AndroidJavaObject>("currentActivity");
        admobPluginClass.CallStatic("AdvHandler", (int)Activity.INSTANTIATE, currActivity, pubID, (int)advSize, (int)advOrient, (int)position_1, (int)position_2, isTesting, testDeviceId, (int)animIn, (int)animOut, (int)levelOfDebug);
        Debug.Log("Instantiate FINISHED");
    }

    /// <summary>
    /// Enable Advertisements, work if not yet called / after calling DisableAdvs();
    /// </summary>
    public static void EnableAds()
    {
        Debug.Log("ENABLED Called");
        admobPluginClass.CallStatic("AdvHandler", (int)Activity.ENABLE, currActivity, "", -1, -1, -1, -1, false, "", -1, -1, -1);
        Debug.Log("ENABLED FINISHED");        
    }
advertisement manager:

using UnityEngine;
using System.Collections;

public class AdvertisementManager : MonoBehaviour {
[SerializeField]
private string m_publisherId = “a14e2fb60918999”;
public string PublisherId
{
get { return m_publisherId; }
set { m_publisherId = value; }
}

    /// <summary>
    /// Advertisement Size
    /// </summary>
    [SerializeField]
    private AdvertisementHandler.AdvSize m_advSize = AdvertisementHandler.AdvSize.SMART_BANNER;
    public AdvertisementHandler.AdvSize AdvSize
    {
        get { return m_advSize; }
        set { m_advSize = value; }
    }

    /// <summary>
    /// Advertisement Orientation
    /// </summary>
    [SerializeField]
    private AdvertisementHandler.AdvOrientation m_orientation = AdvertisementHandler.AdvOrientation.HORIZONTAL;
    public AdvertisementHandler.AdvOrientation Orientation
    {
        get { return m_orientation; }
        set { m_orientation = value; }
    }

    /// <summary>
    /// Advertisement First Position
    /// </summary>
    [SerializeField]
    private AdvertisementHandler.Position m_positionOne = AdvertisementHandler.Position.BOTTOM;
    public AdvertisementHandler.Position PositionOne
    {
        get { return m_positionOne; }
        set { m_positionOne = value; }
    }


    /// <summary>
    /// Advertisement Second Position
    /// </summary>
    [SerializeField]
    private AdvertisementHandler.Position m_positionTwo = AdvertisementHandler.Position.CENTER_HORIZONTAL;
    public AdvertisementHandler.Position PositionTwo
    {
        get { return m_positionTwo; }
        set { m_positionTwo = value; }
    }

    /// <summary>
    /// Set True, if testing game/app
    /// </summary>
    [SerializeField]
    private bool m_isTesting = false;
    public bool IsTesting
    {
        get { return m_isTesting; }
        set { m_isTesting = value; }
    }
    
    /// <summary>
    /// Test Device Id, if you know
    /// </summary>
    [SerializeField]
    private string m_testDeviceId = "4965DFB7E2F16194A15150C45A6927A9";
    public string TestDeviceId
    {
        get { return m_testDeviceId; }
        set { m_testDeviceId = value; }
    }

    /// <summary>
    /// Animation Type when loading new Advertisement
    /// </summary>
    [SerializeField]
    private AdvertisementHandler.AnimationInType m_animationInType = AdvertisementHandler.AnimationInType.SLIDE_IN_LEFT;
    public AdvertisementHandler.AnimationInType AnimationInType
    {
        get { return m_animationInType; }
        set { m_animationInType = value; }
    }

    /// <summary>
    /// Animation Type when unloading current/old Advertisement
    /// </summary>
    [SerializeField]
    private AdvertisementHandler.AnimationOutType m_animationOutType = AdvertisementHandler.AnimationOutType.FADE_OUT;
    public AdvertisementHandler.AnimationOutType AnimationOutType
    {
        get { return m_animationOutType; }
        set { m_animationOutType = value; }
    }
    
    /// <summary>
    /// Level of debug logs
    /// </summary>
    [SerializeField]
    private AdvertisementHandler.LevelOfDebug m_levelOfDebug = AdvertisementHandler.LevelOfDebug.LOW;
    public AdvertisementHandler.LevelOfDebug LevelOfDebug
    {
        get { return m_levelOfDebug; }
        set { m_levelOfDebug = value; }
    }


	// Use this for initialization
	void Start () {
        Debug.Log("Unity Calling Start");
        Debug.Log("Initializing with " + 
            "  Pub ID: " + m_publisherId +
            "  Adv Size: " + m_advSize +
            "  Orientation: " + m_orientation +
            "  Position 1: " + m_positionOne +
            "  Position 2: " + m_positionTwo +
            "  IsTesting: " + m_isTesting +
            "  DeviceID: " + m_testDeviceId + 
            "  AnimIn: " + m_animationInType +
            "  AnimOut: " + m_animationOutType +
            "  LevelOfDebug: " + m_levelOfDebug
            );

        //Initializing Plugin with values
        AdvertisementHandler.Instantiate(m_publisherId, m_advSize, m_orientation, m_positionOne, m_positionTwo, m_isTesting, m_testDeviceId, m_animationInType, m_animationOutType, m_levelOfDebug);

        //Shoot request to enable advertisements
        AdvertisementHandler.EnableAds();
	}
	
}

android manifest:

<?xml version="1.0" encoding="utf-8"?>
<manifest
    xmlns:android="http://schemas.android.com/apk/res/android"
    package="MyBundleIdentifier"
    android:installLocation="preferExternal"
    android:versionCode="2"
    android:versionName="1.1">
    <supports-screens
        android:smallScreens="true"
        android:normalScreens="true"
        android:largeScreens="true"
        android:xlargeScreens="true"
        android:anyDensity="true"/>

    <application
        android:icon="@drawable/app_icon"
        android:label="@string/app_name"
        android:debuggable="true">
        <activity android:name="MyBundleIdentifier.UnityPlayerProxyActivity"
                  android:label="@string/app_name"
                  android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name="MyBundleIdentifier.UnityPlayerActivity"
                  android:label="@string/app_name"
                  android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen">
        </activity>
        <activity android:name="brew.LlamaLoca.UnityPlayerNativeActivity"
                  android:label="@string/app_name"
                  android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen">
            <meta-data android:name="android.app.lib_name" android:value="unity" />
            <meta-data android:name="unityplayer.ForwardNativeEventsToDalvik" android:value="true" />
        </activity>
        <activity android:name="brew.LlamaLoca.VideoPlayer"
                  android:label="@string/app_name"
                  android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen">
        </activity>
        <activity android:name="com.google.ads.AdActivity"
                  android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize"/>
    </application>
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
	<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
</manifest>
Inspector settings of Advertisement handler
![25886-untitled.png|360x465](upload://fvfKRF5MohjF5YX51on0w4uMRRF.png)

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