How to save AndroidManifest.xml file in Unity?

So i’m trying to integrate Admob to Unity and I have tried everything literally everything to do so but nothings seems to work.

But I have noticed one thing that could be the problem…

Everytime I build the game the AndroidManifest.xml is changed back to its default values I mean the problem as you can see down below is with the App ID and the way to add the add is by adding this:

\<meta-data android:name="com.google.android.gms.ads.APPLICATION\_ID" android:value="YOUR\_ADMOB\_APP\_ID"/\>

so I add that meta-data with my AppID of course and then build the game and everytime I go and check the AndroidManifest.xml file I can’t find that meta-data!

So my question is: How to make AndroidManifest.xml actually save these changes?

2019-07-3001:28:10.16826563-26563/? E/AndroidRuntime: FATAL EXCEPTION: mainProcess: com.test.test, PID:26563java.lang.RuntimeException:Unable to get provider com.google.android.gms.ads.MobileAdsInitProvider: java.lang.IllegalStateException:\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*Invalid application ID.Follow instructions here:\*\* https://googlemobileadssdk.page.link/admob-android-update-manifest \*\* to find your app ID.\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\*\* at android.app.ActivityThread.installProvider(ActivityThread.java:7123) at android.app.ActivityThread.installContentProviders(ActivityThread.java:6655) at android.app.ActivityThread.handleBindApplication(ActivityThread.java:6548) at android.app.ActivityThread.access$1900(ActivityThread.java:267) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1963) at android.os.Handler.dispatchMessage(Handler.java:109) at android.os.Looper.loop(Looper.java:207) at android.app.ActivityThread.main(ActivityThread.java:7470) at java.lang.reflect.Method.invoke(NativeMethod) at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:524) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:958)Causedby: java.lang.IllegalStateException: