Even after following the official documentation official documentation

Also After adding style .setStyle(new Notification.DecoratedCustomViewStyle()) from the DecoratedStyle above android 12

Here the the code for custom_notification.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/layout"
    android:layout_width="match_parent"
    android:layout_height="44dp"
    android:padding="10dp" >
    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        style="@style/TextAppearance.Compat.Notification.Title"
        android:textColor="@color/black"/>
    <TextView
        android:id="@+id/text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="12sp"
        android:textColor="@color/black"
        android:layout_below="@id/title"/>
</RelativeLayout>

Here is the code of MainActivity.kt

class MainActivity : AppCompatActivity() {


    @RequiresApi(Build.VERSION_CODES.O)
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        val CHANNEL_ID = "my_channel_01"

        val remoteViews = RemoteViews(packageName, R.layout.custom_notification)
        remoteViews.setTextViewText(R.id.title, "Title")
        remoteViews.setTextViewText(R.id.text, "Text for the notification")

        val mBuilder: NotificationCompat.Builder =
            NotificationCompat.Builder(this, CHANNEL_ID)
                .setSmallIcon(R.drawable.ic_launcher_foreground)
                .setStyle(NotificationCompat.DecoratedCustomViewStyle())
                .setCustomContentView(remoteViews)
                .setCustomBigContentView(remoteViews)
                .setForegroundServiceBehavior(NotificationCompat.FOREGROUND_SERVICE_IMMEDIATE)


        val notificationManager = getSystemService(
            Context.NOTIFICATION_SERVICE
        ) as NotificationManager
        notificationManager.notify(111, mBuilder.build())
    }

In Manifest.xml

> To show notifications above Android 12
      <uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>
> I think its useless, will check it again if this permission is needed or not
        <uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>

Testing on Android 14 by manually giving notification permission from the app settings