Android icon dosent change

Iam using Android Studio i tried using Image Asset,replaceing the image in the folder manually after all that i can see in Android Studio in the Android Mainfest

 android:icon="@drawable/ic_launcher"//i see the image on the side

the i con i created but when i launch the app on my phone i see the Android ic_launcher default icon. i tried to go to Build > Rebuild project and after clean project and even File > invalidated Caches and still i got the Android default icon. When i open the ic_launcher.png in any file in res i can see my own icon but on launch i see the default android icon.

Code: Mainfest

<uses-permission android:name="android.permission.INTERNET" />
<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >

activity_main:

<RelativeLayout xmlns:android="http://ift.tt/nIICcg"
xmlns:tools="http://ift.tt/LrGmb4" android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:icon="@drawable/ic_launcher">//ive tried this but it dosent work either

<WebView
    android:id="@+id/webview"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />