diff --git a/API/Controllers/MangaController.cs b/API/Controllers/MangaController.cs
index 58fc6a5..a413e15 100644
--- a/API/Controllers/MangaController.cs
+++ b/API/Controllers/MangaController.cs
@@ -130,7 +130,7 @@ public class MangaController(MangaContext context) : Controller
         
         if (!System.IO.File.Exists(manga.CoverFileNameInCache))
         {
-            if (Tranga.GetRunningWorkers().Any(worker => worker is DownloadCoverFromMangaconnectorWorker w && w.MangaConnectorId.ObjId == MangaId))
+            if (Tranga.GetRunningWorkers().Any(worker => worker is DownloadCoverFromMangaconnectorWorker w && context.MangaConnectorToManga.Find(w.MangaConnectorIdId)?.ObjId == MangaId))
             {
                 Response.Headers.Append("Retry-After", $"{Tranga.Settings.WorkCycleTimeoutMs * 2 / 1000:D}");
                 return StatusCode(Status503ServiceUnavailable, Tranga.Settings.WorkCycleTimeoutMs * 2  / 1000);
@@ -246,7 +246,7 @@ public class MangaController(MangaContext context) : Controller
         List<Chapter> chapters = manga.Chapters.ToList();
         if (chapters.Count == 0)
         {
-            if (Tranga.GetRunningWorkers().Any(worker => worker is RetrieveMangaChaptersFromMangaconnectorWorker w && w.MangaConnectorId.ObjId == MangaId && w.State < WorkerExecutionState.Completed))
+            if (Tranga.GetRunningWorkers().Any(worker => worker is RetrieveMangaChaptersFromMangaconnectorWorker w && context.MangaConnectorToManga.Find(w.MangaConnectorIdId)?.ObjId == MangaId && w.State < WorkerExecutionState.Completed))
             {
                 Response.Headers.Append("Retry-After", $"{Tranga.Settings.WorkCycleTimeoutMs * 2 / 1000:D}");
                 return StatusCode(Status503ServiceUnavailable, Tranga.Settings.WorkCycleTimeoutMs * 2/ 1000);
@@ -284,7 +284,7 @@ public class MangaController(MangaContext context) : Controller
         List<Chapter> chapters = manga.Chapters.ToList();
         if (chapters.Count == 0)
         {
-            if (Tranga.GetRunningWorkers().Any(worker => worker is RetrieveMangaChaptersFromMangaconnectorWorker w && w.MangaConnectorId.ObjId == MangaId && w.State < WorkerExecutionState.Completed))
+            if (Tranga.GetRunningWorkers().Any(worker => worker is RetrieveMangaChaptersFromMangaconnectorWorker w && context.MangaConnectorToManga.Find(w.MangaConnectorIdId)?.ObjId == MangaId && w.State < WorkerExecutionState.Completed))
             {
                 Response.Headers.Append("Retry-After", $"{Tranga.Settings.WorkCycleTimeoutMs * 2 / 1000:D}");
                 return StatusCode(Status503ServiceUnavailable, Tranga.Settings.WorkCycleTimeoutMs * 2/ 1000);
diff --git a/API/Workers/MangaDownloadWorkers/DownloadChapterFromMangaconnectorWorker.cs b/API/Workers/MangaDownloadWorkers/DownloadChapterFromMangaconnectorWorker.cs
index 3aae423..0328def 100644
--- a/API/Workers/MangaDownloadWorkers/DownloadChapterFromMangaconnectorWorker.cs
+++ b/API/Workers/MangaDownloadWorkers/DownloadChapterFromMangaconnectorWorker.cs
@@ -14,9 +14,11 @@ namespace API.Workers;
 public class DownloadChapterFromMangaconnectorWorker(MangaConnectorId<Chapter> chId, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn)
 {
-    public MangaConnectorId<Chapter> MangaConnectorId { get; init; } = chId;
+    internal readonly string MangaConnectorIdId = chId.Key;
     protected override BaseWorker[] DoWorkInternal()
     {
+        if (DbContext.MangaConnectorToChapter.Find(MangaConnectorIdId) is not { } MangaConnectorId)
+            return []; //TODO Exception?
         MangaConnector mangaConnector = MangaConnectorId.MangaConnector;
         Chapter chapter = MangaConnectorId.Obj;
         if (chapter.Downloaded)
@@ -179,5 +181,5 @@ public class DownloadChapterFromMangaconnectorWorker(MangaConnectorId<Chapter> c
         return true;
     }
 
-    public override string ToString() => $"{base.ToString()} {MangaConnectorId}";
+    public override string ToString() => $"{base.ToString()} {MangaConnectorIdId}";
 }
\ No newline at end of file
diff --git a/API/Workers/MangaDownloadWorkers/DownloadCoverFromMangaconnectorWorker.cs b/API/Workers/MangaDownloadWorkers/DownloadCoverFromMangaconnectorWorker.cs
index 1a5ed3e..ba07613 100644
--- a/API/Workers/MangaDownloadWorkers/DownloadCoverFromMangaconnectorWorker.cs
+++ b/API/Workers/MangaDownloadWorkers/DownloadCoverFromMangaconnectorWorker.cs
@@ -6,9 +6,11 @@ namespace API.Workers;
 public class DownloadCoverFromMangaconnectorWorker(MangaConnectorId<Manga> mcId, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn)
 {
-    public MangaConnectorId<Manga> MangaConnectorId { get; init; } = mcId;
+    internal readonly string MangaConnectorIdId = mcId.Key;
     protected override BaseWorker[] DoWorkInternal()
     {
+        if (DbContext.MangaConnectorToManga.Find(MangaConnectorIdId) is not { } MangaConnectorId)
+            return []; //TODO Exception?
         MangaConnector mangaConnector = MangaConnectorId.MangaConnector;
         Manga manga = MangaConnectorId.Obj;
         
@@ -18,5 +20,5 @@ public class DownloadCoverFromMangaconnectorWorker(MangaConnectorId<Manga> mcId,
         return [];
     }
     
-    public override string ToString() => $"{base.ToString()} {MangaConnectorId}";
+    public override string ToString() => $"{base.ToString()} {MangaConnectorIdId}";
 }
\ No newline at end of file
diff --git a/API/Workers/MangaDownloadWorkers/RetrieveMangaChaptersFromMangaconnectorWorker.cs b/API/Workers/MangaDownloadWorkers/RetrieveMangaChaptersFromMangaconnectorWorker.cs
index 5e95f11..ec03b95 100644
--- a/API/Workers/MangaDownloadWorkers/RetrieveMangaChaptersFromMangaconnectorWorker.cs
+++ b/API/Workers/MangaDownloadWorkers/RetrieveMangaChaptersFromMangaconnectorWorker.cs
@@ -6,9 +6,11 @@ namespace API.Workers;
 public class RetrieveMangaChaptersFromMangaconnectorWorker(MangaConnectorId<Manga> mcId, string language, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn)
 {
-    public MangaConnectorId<Manga> MangaConnectorId { get; init; } = mcId;
+    internal readonly string MangaConnectorIdId = mcId.Key;
     protected override BaseWorker[] DoWorkInternal()
     {
+        if (DbContext.MangaConnectorToManga.Find(MangaConnectorIdId) is not { } MangaConnectorId)
+            return []; //TODO Exception?
         MangaConnector mangaConnector = MangaConnectorId.MangaConnector;
         Manga manga = MangaConnectorId.Obj;
         // This gets all chapters that are not downloaded
@@ -29,5 +31,5 @@ public class RetrieveMangaChaptersFromMangaconnectorWorker(MangaConnectorId<Mang
         return [];
     }
 
-    public override string ToString() => $"{base.ToString()} {MangaConnectorId}";
+    public override string ToString() => $"{base.ToString()} {MangaConnectorIdId}";
 }
\ No newline at end of file
diff --git a/API/Workers/MoveMangaLibraryWorker.cs b/API/Workers/MoveMangaLibraryWorker.cs
index 170b611..4367443 100644
--- a/API/Workers/MoveMangaLibraryWorker.cs
+++ b/API/Workers/MoveMangaLibraryWorker.cs
@@ -5,8 +5,14 @@ namespace API.Workers;
 public class MoveMangaLibraryWorker(Manga manga, FileLibrary toLibrary, IEnumerable<BaseWorker>? dependsOn = null)
     : BaseWorkerWithContext<MangaContext>(dependsOn)
 {
+    internal readonly string MangaId = manga.Key;
+    internal readonly string LibraryId = toLibrary.Key;
     protected override BaseWorker[] DoWorkInternal()
     {
+        if (DbContext.Mangas.Find(MangaId) is not { } manga)
+            return []; //TODO Exception?
+        if (DbContext.FileLibraries.Find(LibraryId) is not { } toLibrary)
+            return []; //TODO Exception?
         Dictionary<Chapter, string> oldPath = manga.Chapters.ToDictionary(c => c, c => c.FullArchiveFilePath);
         manga.Library = toLibrary;
 
@@ -16,5 +22,5 @@ public class MoveMangaLibraryWorker(Manga manga, FileLibrary toLibrary, IEnumera
         return manga.Chapters.Select(c => new MoveFileOrFolderWorker(c.FullArchiveFilePath, oldPath[c])).ToArray<BaseWorker>();
     }
 
-    public override string ToString() => $"{base.ToString()} {manga} {toLibrary}";
+    public override string ToString() => $"{base.ToString()} {MangaId} {LibraryId}";
 }
\ No newline at end of file