The message "Cannot find iBeacon" is displayed

My question is very simple. I would like to display an error message, that is, "Can't find iBeacon" if iBeacon Monitoring fails, after being called startSearchingForSessions

with a button click after calling inviewDidLoad

override func viewDidLoad() {
    super.viewDidLoad()

    self.locationManager = CLLocationManager()
    if self.locationManager.responds(to: #selector(CLLocationManager.requestWhenInUseAuthorization)) {
        self.locationManager.requestWhenInUseAuthorization()
    }
    self.locationManager.delegate = self
    self.locationManager.pausesLocationUpdatesAutomatically = false

    let uuid = UUID(uuidString: "869A6E2E-AE14-4CF5-8313-8D6976058A7A")
    self.beaconRegion = CLBeaconRegion(proximityUUID: uuid!, identifier: "com.dejordan.myapp"
    startSearchingForSessions()

}

func startSearchingForSessions() {

    // Start looking for the beacons with that UUID and Identifier.
    self.locationManager.startMonitoring(for: self.beaconRegion)
    self.locationManager.startRangingBeacons(in: self.beaconRegion)
    self.locationManager.startUpdatingLocation()

}

      

        
        
        
      

    

And processing the found lighthouses in this way:

// Required by the Location Manager.
func locationManager(_ manager: CLLocationManager, didEnterRegion region: CLRegion) {
    self.locationManager.startRangingBeacons(in: self.beaconRegion)
}

func locationManager(_ manager: CLLocationManager, didDetermineState state: CLRegionState, for region: CLRegion) {
    if state == CLRegionState.outside {
        print("Cannot Find Beacon")
    }
}

// Required by the Location Manager.
func locationManager(_ manager: CLLocationManager, didExitRegion region: CLRegion) {
    self.locationManager.stopRangingBeacons(in: self.beaconRegion)
}

// This is called if any beacons are found.
func locationManager(_ manager: CLLocationManager, didRangeBeacons beacons: [CLBeacon], in region: CLBeaconRegion) {

    var result = Array<CLBeacon>()
    for beacon in beacons {
        result.append(beacon)
    }

    foundBeacons = result
    // If we found any, we need to see
    // what class they belong to based on information
    // from Parse.
    self.identifyFoundBeacons()

    // We can stop looking for beacons now.
    self.locationManager.stopMonitoring(for: self.beaconRegion)
    self.locationManager.stopRangingBeacons(in: self.beaconRegion)
    self.locationManager.stopUpdatingLocation()

}

      

        
        
        
      

    

I've applied the delegate error methods trying to find where this is happening, but so far in navigating the mound of documentation on iBeacon I've come to fruitless.

func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
    print("Location manager failed: \(error.localizedDescription)")
}

func locationManager(_ manager: CLLocationManager, monitoringDidFailFor region: CLRegion?, withError error: Error) {
    print("Failed monitoring region: \(error.localizedDescription)")
}

      

        
        
        
      

    

Thank!