Use onLocationChanged() updates inside a foreground service

I'm trying to create a foreground service that can track the user's location with the phone's GPS. I have a ForegroundService class, where in the onCreate() method I call a function that should start by asking for location updates:

fusedLocationProviderClient = LocationServices.getFusedLocationProviderClient(this)

locationManager = getSystemService(LOCATION_SERVICE) as LocationManager

val locationListener: LocationListener = this
locationManager.requestLocationUpdates(
    LocationManager.GPS_PROVIDER, 2000, 0F, locationListener
)

My class is implementing Service() and LocationListener. I then override onLocationChanged, where I should log the current speed (and leave onAccuracyChanged empty).

Of course I have a notification correctly showing in android, so the service is definitely running, but I seem to get no location updates anyways. What could the problem be? Thank you.

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