CompanionDeviceService unbinds immediately

I'm trying to implement CompanionDeviceService in order to interact with our BLE device. According to the documentation

System will keep this service bound whenever an associated device is nearby, ensuring app stays alive

But that's not what I'm seeing

17:47:48.563 MyCompanionDeviceService: onDeviceAppeared FF:FF:6D:10:F1:16
17:47:48.565 MyCompanionDeviceService: onUnbind
17:47:48.568 MyCompanionDeviceService: onDestroy

Around 1 minute later, onDeviceAppeared is invoked again, with the same result.

FF:FF:6D:10:F1:16 is not bonded. createBond is never invoked on BleDevice. I haven't found whether this is relevant or not.

I'm running on a Pixel 4a on latest available Android 12 version

Edit: Adding more code for reference

Manifest

<uses-permission android:name="android.permission.REQUEST_COMPANION_RUN_IN_BACKGROUND" />
<uses-permission android:name="android.permission.REQUEST_COMPANION_USE_DATA_IN_BACKGROUND" />
<uses-permission android:name="android.permission.REQUEST_OBSERVE_COMPANION_DEVICE_PRESENCE" />


<service
  android:name="com.mycompany.MyCompanionDeviceService"
  android:exported="true"
 android:permission="android.permission.BIND_COMPANION_DEVICE_SERVICE">
      <intent-filter>
        <action android:name="android.companion.CompanionDeviceService" />
      </intent-filter>
</service>

The startObservingDevicePresence succeeds, otherwise my service wouldn't be called at all

And there's nothing relevant on the service

@RequiresApi(Build.VERSION_CODES.S)
internal class MyCompanionDeviceService : CompanionDeviceService() {   

    override fun onCreate() {
        appComponent.inject(this)
        super.onCreate()
    }

    override fun onUnbind(intent: Intent?): Boolean {
        Timber.d("onUnbind")
        return super.onUnbind(intent)
    }

    override fun onDeviceAppeared(address: String) {
        Timber.d("onDeviceAppeared $address")
    }    

    override fun onDeviceDisappeared(address: String) {
        Timber.tag("companionservice").d("onDeviceDisappeared $address")
    }

    override fun onDestroy() {
        super.onDestroy()

        Timber.d("onDestroy")
    }
}