diff --git a/Covid19Radar/Covid19Radar.Android/MainApplication.cs b/Covid19Radar/Covid19Radar.Android/MainApplication.cs
index 4a26647bb..8d4c5f2e1 100644
--- a/Covid19Radar/Covid19Radar.Android/MainApplication.cs
+++ b/Covid19Radar/Covid19Radar.Android/MainApplication.cs
@@ -49,7 +49,7 @@ private Lazy<AbsExposureDetectionBackgroundService> _exposureDetectionBackground
         private readonly Lazy<AbsEventLogSubmissionBackgroundService> _eventLogSubmissionBackgroundService
             = new Lazy<AbsEventLogSubmissionBackgroundService>(() => ContainerLocator.Current.Resolve<AbsEventLogSubmissionBackgroundService>());
 
-        private Lazy<AbsDataMaintainanceBackgroundService> _dataMaintainanceService
+        private readonly Lazy<AbsDataMaintainanceBackgroundService> _dataMaintainanceService
             = new Lazy<AbsDataMaintainanceBackgroundService>(() => ContainerLocator.Current.Resolve<AbsDataMaintainanceBackgroundService>());
 
         private Lazy<ILoggerService> _loggerService
diff --git a/Covid19Radar/Covid19Radar.iOS/AppDelegate.cs b/Covid19Radar/Covid19Radar.iOS/AppDelegate.cs
index 3ebfa7aff..b989d2dd0 100644
--- a/Covid19Radar/Covid19Radar.iOS/AppDelegate.cs
+++ b/Covid19Radar/Covid19Radar.iOS/AppDelegate.cs
@@ -44,7 +44,7 @@ private Lazy<AbsExposureDetectionBackgroundService> _exposureDetectionBackground
         private readonly Lazy<AbsEventLogSubmissionBackgroundService> _eventLogSubmissionBackgroundService
             = new Lazy<AbsEventLogSubmissionBackgroundService>(() => ContainerLocator.Current.Resolve<AbsEventLogSubmissionBackgroundService>());
 
-        private Lazy<AbsDataMaintainanceBackgroundService> _dataMaintainanceBackgroundService
+        private readonly Lazy<AbsDataMaintainanceBackgroundService> _dataMaintainanceBackgroundService
             = new Lazy<AbsDataMaintainanceBackgroundService>(() => ContainerLocator.Current.Resolve<AbsDataMaintainanceBackgroundService>());
 
         private Lazy<IExposureDetectionService> _exposureDetectionService
diff --git a/Covid19Radar/Covid19Radar/Services/AbsDataMaintainanceBackgroundService.cs b/Covid19Radar/Covid19Radar/Services/AbsDataMaintainanceBackgroundService.cs
index 0a034e26e..eefa1c0e1 100644
--- a/Covid19Radar/Covid19Radar/Services/AbsDataMaintainanceBackgroundService.cs
+++ b/Covid19Radar/Covid19Radar/Services/AbsDataMaintainanceBackgroundService.cs
@@ -15,7 +15,7 @@ public abstract class AbsDataMaintainanceBackgroundService : IBackgroundService
 
         private readonly IEventLogRepository _eventLogRepository;
 
-        public AbsDataMaintainanceBackgroundService(
+        protected AbsDataMaintainanceBackgroundService(
             ILoggerService loggerService,
             IEventLogRepository eventLogRepository)
         {