Error in android url scheme

Hi

I'm trying to make custom URL Scheme In Android

When I create a new xamarin forms app and add this code to manifest

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="com.companyname.app7">
    <uses-sdk android:minSdkVersion="21" android:targetSdkVersion="28" />
    <application android:label="App7.Android">
         <activity  android:name="com.companyname.app7.MainActivity">
          <intent-filter>
            <action android:name="android.intent.action.VIEW" />
            <category android:name="android.intent.category.DEFAULT" />
            <category android:name="android.intent.category.BROWSABLE" />
            <data android:scheme="myapp" />
          </intent-filter>
        </activity>
     </application>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
</manifest>

And I call the app by clicking a link

<a href="myapp://hello-world"> Circle Here</a>

I get this error

Java.Lang.RuntimeException: 'Unable to instantiate activity ComponentInfo{com.companyname.app7/com.companyname.app7.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.companyname.app7.MainActivity" on path: DexPathList[[zip file "/data/app/com.companyname.app7-1/base.apk"],nativeLibraryDirectories=[/data/app/com.companyname.app7-1/lib/arm, /data/app/com.companyname.app7-1/base.apk!/lib/armeabi-v7a, /vendor/lib, /system/lib]]'