I have cobbled together for my first swift app the following code, If i am at the location coordinates with the app closed when the notification event is fired the notification is delivered correctly, in every other scenario it fails, i have Location Updates and Background Fetch enabled in the Background Modes section.

Any pointers hugely appreciated, thank you.

import SwiftUI
import WebKit
import CoreLocation
import UserNotifications

let locationManager = CLLocationManager()


struct ContentView: View {
    @StateObject private var locationManager = LocationManager()

    var body: some View {
        WebView(url: URL(string: "https://www.website.uk")!)
            .edgesIgnoringSafeArea(.all)
            .onAppear {
                locationManager.requestPermissions()
            }
    }
}

struct WebView: UIViewRepresentable {
    var url: URL

    func makeUIView(context: Context) -> WKWebView {
        WKWebView()
    }

    func updateUIView(_ uiView: WKWebView, context: Context) {
        let request = URLRequest(url: url)
        uiView.load(request)
    }
}

@main
struct NotificationTestApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

class LocationManager: NSObject, CLLocationManagerDelegate, ObservableObject {
    private var locationManager = CLLocationManager()

    override init() {
        super.init()
        locationManager.delegate = self
    }
    
    func triggerNotification(_ password: String)
    {
        let center = UNUserNotificationCenter.current()
        let content = UNMutableNotificationContent()
        content.title = "My First Notification"
        content.body = password
        content.sound = UNNotificationSound.default
        content.subtitle = "Hello World"
        content.userInfo = ["value": "Data with local notification"]
        
        let fireDate = Calendar.current.dateComponents([.day, .month, .year, .hour, .minute, .second], from: Date().addingTimeInterval(10))
        let trigger = UNCalendarNotificationTrigger(dateMatching: fireDate, repeats: true)
        let request = UNNotificationRequest(identifier: "reminder", content: content, trigger: trigger)

        center.add(request)
        {
            (error) in
            if error != nil
            {
                print("Error = (error?.localizedDescription ?? "error in local notification") ")
            }
        }
    }
    
    func locationManager(_ manager: CLLocationManager, didEnterRegion region: CLRegion) {
        if region.identifier == "LOC1"
        {
            triggerNotification("Boo: " + Date().formatted())
        }
    }
    
    func locationManager(_ manager: CLLocationManager, didExitRegion region: CLRegion) {
        if region.identifier == "LOC1"
        {
            //reset the region state
            locationManager.stopMonitoring(for: region)
            locationManager.startMonitoring(for: region)
        }
    }
    
    func locationManager(_ manager: CLLocationManager, monitoringDidFailFor region: CLRegion?, withError error: Error) {
        print("Failed to monitor region: (error.localizedDescription)")
    }

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

    func requestPermissions() {
        locationManager.requestWhenInUseAuthorization()
        
        UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .badge, .sound]) { granted, error in
            if granted {
                print("Notification permission granted.")
                
                //self.triggerNotification("Test")
                
            } else if let error = error {
                print("Notification permission denied with error: (error.localizedDescription)")
            }
        }
        //Setup Geofence
        let locationCoordinates = CLLocationCoordinate2D(latitude: 50.1234, longitude: -1.2345)
        let geofenceRegion = CLCircularRegion(center: locationCoordinates, radius: 500, identifier: "LOC1")
        geofenceRegion.notifyOnEntry = true
        geofenceRegion.notifyOnEntry = true
        
        locationManager.startMonitoring(for: geofenceRegion)
    }
}