Android studio 3.6 cannot resolve symbol generated by view binding

Question

I am implementing view binding and I have problem with Cannot resolve some symbols. For some Views the IDE writes to me: Cannot resolve symbol.

Activity: ActivityMain

public class ActivityMain extends AppCompatActivity {

    private ActivityMainBinding viewBinding;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        // Set activity layout.
        viewBinding = ActivityMainBinding.inflate(getLayoutInflater());
        View view = viewBinding.getRoot();
        setContentView(view);

        new AdAdaptiveKt(this, viewBinding.adViewContainer); //<<== Cannot resolve symbol viewBinding.adViewContainer

    }


}

Layout activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/mainFrameLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:clickable="true"
    android:focusable="true">

    ...

            <FrameLayout
                android:id="@+id/adViewContainer"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_gravity="center_horizontal"
                />
     ...
</FrameLayout>

When I find the generated file:
/home/XXX/android-projects/XXX/app/build/generated/data_binding_base_class_source_out/debug/out/XX/XXX/XXX/databinding/ActivityMainBinding.java:

public final class ActivityMainBinding implements ViewBinding {

    ...

  @NonNull
  public final FrameLayout adViewContainer;

   ...
}

All Views are generated correctly. Build is OK and I can run project in a real device. But Android Studio still writes me: Cannot resolve symbol.

Android studio 3.6.3,
Android gradle plugin 3.6.3,
Gradle: tested: 5.6.4 - 6.3

I tried:

• clean project, rebuild,
• Invalidate caches and restart,
• Import project
• Delete .idea and .gradle project directories
• Delete directory /home/XXX/.gradle and open project
• Open project in Android Studio 4.0-beta1 and 4.1-canary2

Problem solved
I had comment (<!--&&-->) in layout and viewBinding does not work properly. I do not why? Could anybody verify it?