I am developing an application using .NET MAUI that needs to continuously listen for missed calls and send the caller’s phone number to an API endpoint. I have implemented a foreground service to keep the app running in the background. The service works for a few minutes, but then stops running when the device goes into idle mode or when the app is not opened, resulting in missed API calls.

I have tried using a foreground service with a persistent notification, but it does not seem to keep the service running consistently. Here is my implementation:

I need the service to continuously run in the background and listen for missed calls even when the phone is idle or the app is not opened. I also want to ensure that the necessary permissions are requested and granted, including notification access permissions. What changes or best practices should I follow to achieve this?

`**MainActivity.cs**
using Android;
using Android.App;
using Android.Content;
using Android.Content.PM;
using Android.OS;
using Android.Provider; // For Settings.Secure
using AndroidX.Core.App;
using AndroidX.Core.Content;
using Android.Widget;

namespace MissedCallSMSService.Platforms.Android
{
    [Activity(Label = "MissedCallSMSService", MainLauncher = true)]
    public class MainActivity : Activity
    {
        const int RequestCallLogPermissionId = 0;
        const int RequestNotificationAccessId = 1;

        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);

            // Start the MissedCallService
            StartMissedCallService();

            // Check and request permissions
            CheckAndRequestPermissions();
        }

        private void StartMissedCallService()
        {
            Intent serviceIntent = new Intent(this, typeof(MissedCallService));
            if (Build.VERSION.SdkInt >= BuildVersionCodes.O)
            {
                StartForegroundService(serviceIntent);
            }
            else
            {
                StartService(serviceIntent);
            }
        }

        void CheckAndRequestPermissions()
        {
            if (ContextCompat.CheckSelfPermission(this, Manifest.Permission.ReadPhoneState) != Permission.Granted ||
                ContextCompat.CheckSelfPermission(this, Manifest.Permission.ReadCallLog) != Permission.Granted)
            {
                ActivityCompat.RequestPermissions(this, new string[]
                {
                    Manifest.Permission.ReadPhoneState,
                    Manifest.Permission.ReadCallLog
                }, RequestCallLogPermissionId);
            }
            else
            {
                CheckAndRequestNotificationPermission();
            }
        }

        void CheckAndRequestNotificationPermission()
        {
            if (!IsNotificationServiceEnabled())
            {
                // Guide the user to the notification access settings
                Intent intent = new Intent(Settings.ActionNotificationListenerSettings);
                StartActivityForResult(intent, RequestNotificationAccessId);
            }
        }

        public override void OnRequestPermissionsResult(int requestCode, string[] permissions, Permission[] grantResults)
        {
            base.OnRequestPermissionsResult(requestCode, permissions, grantResults);

            if (requestCode == RequestCallLogPermissionId)
            {
                if (grantResults.Length > 0 && grantResults[0] == Permission.Granted)
                {
                    // Permissions granted
                    CheckAndRequestNotificationPermission();
                }
                else
                {
                    // Permissions denied
                    Toast.MakeText(this, "Permissions denied. The app requires call log access to function properly.", ToastLength.Long).Show();
                }
            }
        }

        private bool IsNotificationServiceEnabled()
        {
            string pkgName = PackageName;
            string flat = Settings.Secure.GetString(ContentResolver, "enabled_notification_listeners");
            if (flat != null && flat.Contains(pkgName))
            {
                return true;
            }
            return false;
        }
    }
}

**MissedCallService.cs**
using Android;
using Android.App;
using Android.Content;
using Android.Content.PM;
using Android.OS;
using Android.Util;
using AndroidX.Core.App;
using AndroidX.Core.Content;
using System.Threading;
using System.Threading.Tasks;

namespace MissedCallSMSService.Platforms.Android
{
    [Service]
    public class MissedCallService : Service
    {
        private MissedCallReceiver mReceiver;
        private const int NotificationId = 1;
        private string NOTIFICATION_CHANNEL_ID = "1000";
        private int NOTIFICATION_ID = 1;
        private string NOTIFICATION_CHANNEL_NAME = "notification";

        public override IBinder OnBind(Intent intent)
        {
            return null;
        }

        public override StartCommandResult OnStartCommand(Intent intent, StartCommandFlags flags, int startId)
        {
            // Run the service in the foreground to ensure it continues running
            Notification notification = new NotificationCompat.Builder(this, "missed_call_channel")
                .SetContentTitle("Missed Call Service")
                .SetContentText("Listening for missed calls")
                .SetSmallIcon(Resource.Drawable.maui_splash_image)
                .Build();

            // StartForeground(NotificationId, notification);
            StartForegroundService();

            // Start listening for missed calls
            ListenForMissedCalls();

            return StartCommandResult.Sticky;
        }

        private void StartForegroundService()
        {
            var notifcationManager = GetSystemService(Context.NotificationService) as NotificationManager;

            if (Build.VERSION.SdkInt >= BuildVersionCodes.O)
            {
                CreateNotificationChannel(notifcationManager);
            }

            var notification = new NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID);
            notification.SetAutoCancel(false);
            notification.SetOngoing(true);
            notification.SetSmallIcon(Resource.Mipmap.appicon);
            notification.SetContentTitle("ForegroundService");
            notification.SetContentText("Foreground Service is running");
            StartForeground(NOTIFICATION_ID, notification.Build());
        }

        private void CreateNotificationChannel(NotificationManager notificationManager)
        {
            var channel = new NotificationChannel(NOTIFICATION_CHANNEL_ID, NOTIFICATION_CHANNEL_NAME,
            NotificationImportance.High);
            notificationManager.CreateNotificationChannel(channel);
        }

        private void ListenForMissedCalls()
        {
            mReceiver = new MissedCallReceiver();

            var filter = new IntentFilter();
            filter.AddAction("android.intent.action.PHONE_STATE");

            RegisterReceiver(mReceiver, filter);

            // Check periodically if permissions are granted and notify if not
            Task.Run(() =>
            {
                while (true)
                {
                    Thread.Sleep(5000); // Sleep for 5 seconds before checking again

                    if (ContextCompat.CheckSelfPermission(this, Manifest.Permission.ReadPhoneState) != Permission.Granted ||
                        ContextCompat.CheckSelfPermission(this, Manifest.Permission.ReadCallLog) != Permission.Granted)
                    {
                        NotifyUserToGrantPermissions();
                    }
                }
            });
        }

        private void NotifyUserToGrantPermissions()
        {
            NotificationManager notificationManager = (NotificationManager)GetSystemService(NotificationService);

            if (Build.VERSION.SdkInt >= BuildVersionCodes.O)
            {
                var channel = new NotificationChannel("missed_call_channel", "Missed Call Channel", NotificationImportance.High)
                {
                    Description = "Notifications for missed call permissions"
                };
                notificationManager.CreateNotificationChannel(channel);
            }

            var notificationIntent = new Intent(this, typeof(MainActivity));
            notificationIntent.SetFlags(ActivityFlags.NewTask | ActivityFlags.ClearTask);
            var pendingIntent = PendingIntent.GetActivity(this, 0, notificationIntent, PendingIntentFlags.UpdateCurrent);

            var builder = new NotificationCompat.Builder(this, "missed_call_channel")
                .SetContentTitle("Missed Call Service")
                .SetContentText("Please grant phone state and call log permissions.")
                .SetSmallIcon(Resource.Drawable.maui_splash_image)
                .SetContentIntent(pendingIntent)
                .SetAutoCancel(true);

            notificationManager.Notify(NotificationId, builder.Build());
        }

        public override void OnDestroy()
        {
            base.OnDestroy();
            if (mReceiver != null)
            {
                UnregisterReceiver(mReceiver);
            }
        }
    }
}`