I'm tinkering with nats.io as an alternative to Firebase Cloud Messaging

Here's the MainActivity:

mport android.content.Intent
import android.os.Build
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import android.widget.Button
import androidx.work.ExistingWorkPolicy
import androidx.work.OneTimeWorkRequest
import androidx.work.WorkManager


class MainActivity : AppCompatActivity() {

    lateinit var btnStart: Button
    lateinit var btnStop: Button

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)

        btnStart = findViewById<Button>(R.id.btnStartService)
        btnStop = findViewById<Button>(R.id.btnStopService)

        btnStart.setOnClickListener {
            Log.d("ENDLESS_SERVICE","START THE FOREGROUND SERVICE ON DEMAND")
            actionOnService(Actions.START_SERVICE)

            WorkManager.getInstance(this)
                .beginUniqueWork("MyBackgroundWorker", ExistingWorkPolicy.APPEND_OR_REPLACE,
                    OneTimeWorkRequest.from(MyBackgroundWorker::class.java)).enqueue().state
                .observe(this) { state ->
                    Log.d("NATSDemo", "MyBackgroundWorker: $state")
                }

        }

        btnStop.setOnClickListener {
            Log.d("ENDLESS_SERVICE","START THE FOREGROUND SERVICE ON DEMAND")
            actionOnService(Actions.STOP_SERVICE)
        }
    }

    private fun actionOnService(action: Actions) {
        if (getServiceState(this) == ServiceState.SERVICE_STOPPED && action == Actions.STOP_SERVICE) return
        Intent(this, EndlessService::class.java).also {
            it.action = action.name
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                Log.d("ENDLESS_SERVICE","Starting the service in >=26 Mode")
                startForegroundService(it)
                return
            }
            Log.d("ENDLESS_SERVICE", "Starting the service in < 26 Mode")
            startService(it)
        }
    }
}

If you take a look at the whole code, you'll notice the NATS connection is initiated each 3 minutes. I send messages using nats-cli, and interestingly, all the notifications appear in the Android notification tray have the title "NATS Demo" (from EndlessService.kt), but not even one from MyBackgroundWorker.kt, which has the title "Message from NATS". So MyBackgroundWorker is not executed at all. Why?

BTW, I found this on logcat, probably could be a useful hint:

2022-01-13 01:58:13.926 19560-19592/com.anta40.app.natsservicedemo I/WM-WorkerWrapper: Worker result SUCCESS for Work [ id=18c9ba36-a578-4957-b7f6-9205ef6183c9, tags={ com.anta40.app.natsservicedemo.MyBackgroundWorker } ]
2022-01-13 01:58:13.927 19560-19560/com.anta40.app.natsservicedemo I/WM-SystemFgDispatcher: Started foreground service Intent { act=ACTION_START_FOREGROUND cmp=com.anta40.app.natsservicedemo/androidx.work.impl.foreground.SystemForegroundService (has extras) }
2022-01-13 01:58:13.941 19560-19560/com.anta40.app.natsservicedemo I/WM-SystemFgDispatcher: Stopping foreground service