Wear OS: notifications won't show

I am developing a stand alone app on Wear OS (Android 8+) and I have issues with notifications.

I am running a Foreground Service, with an on-going notification. That on-going notification works very well and has no feature from the Wear OS (so the code can work on standalone Android).

However, whenever I want to display other notifications, it is impossible.

No error message, nothing: my notifications are not displayed. I made sure to create separate channels and to have them enabled (via the settings).

Here is my code, running in the Looper.mainLooper() via a Handler.

final Notification notification = new NotificationCompat.Builder(MonitorService.this, LOGS_CHANNEL_ID)
                        .setSmallIcon(R.drawable.ic_backup_logs) // vector (doesn't work with png as well)
                        .setContentTitle(getString(R.string.monitor_service_notification_log_file_backed_up_process))
                        .setContentText("test")
                        .setPriority(NotificationCompat.PRIORITY_HIGH)
                        .build();

notificationManagerCompat.notify(LOGS_ID, notification); // unique final static id

Am I missing something here ?

Thanks for the help !

Use this code

Notification.Builder b = new Notification.Builder(ctx);

    //FIX android O bug Notification add setChannelId("shipnow-message")
    NotificationChannel mChannel = null;
    b.setSmallIcon(R.drawable.ic_backup_logs) // vector (doesn't work with png as well)
                    .setContentTitle(getString(R.string.monitor_service_notification_log_file_backed_up_process))
                    .setContentText("test")
                    .setPriority(NotificationCompat.PRIORITY_HIGH)
            .setSound(RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION));

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        mChannel = new NotificationChannel("your-channel", "yourSubjectName",NotificationManager.IMPORTANCE_HIGH);
        b.setChannelId("your-channel");
    }

    NotificationManager notificationManager = (NotificationManager) ctx.getSystemService(Context.NOTIFICATION_SERVICE);
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        notificationManager.createNotificationChannel(mChannel);
    }
    notificationManager.notify(id, b.build());