diff --git a/Tranga/Manga.cs b/Tranga/Manga.cs
index 357f940..6989d7d 100644
--- a/Tranga/Manga.cs
+++ b/Tranga/Manga.cs
@@ -67,7 +67,7 @@ public struct Manga
         while (this.folderName.EndsWith('.'))
             this.folderName = this.folderName.Substring(0, this.folderName.Length - 1);
         string onlyLowerLetters = string.Concat(this.sortName.ToLower().Where(Char.IsLetter));
-        this.internalId = Convert.ToBase64String(Encoding.ASCII.GetBytes($"{onlyLowerLetters}{this.year}"));
+        this.internalId = DateTime.Now.Ticks.ToString();
         this.ignoreChaptersBelow = ignoreChaptersBelow ?? 0f;
         this.latestChapterDownloaded = 0;
         this.latestChapterAvailable = 0;
diff --git a/Tranga/MangaConnectors/MangaConnectorJsonConverter.cs b/Tranga/MangaConnectors/MangaConnectorJsonConverter.cs
index 2213a48..3b3e6da 100644
--- a/Tranga/MangaConnectors/MangaConnectorJsonConverter.cs
+++ b/Tranga/MangaConnectors/MangaConnectorJsonConverter.cs
@@ -1,4 +1,6 @@
-using Newtonsoft.Json;
+using System.Data;
+using System.Diagnostics;
+using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 
 namespace Tranga.MangaConnectors;
@@ -22,29 +24,22 @@ public class MangaConnectorJsonConverter : JsonConverter
     public override object ReadJson(JsonReader reader, Type objectType, object? existingValue, JsonSerializer serializer)
     {
         JObject jo = JObject.Load(reader);
-        switch (jo.GetValue("name")!.Value<string>()!)
+        string? connectorName = jo.Value<string>("name");
+        if (connectorName is null)
+            throw new ConstraintException("Name can not be null.");
+        return connectorName switch
         {
-            case "MangaDex":
-                return this._connectors.First(c => c is MangaDex);
-            case "Manganato":
-                return this._connectors.First(c => c is Manganato);
-            case "MangaKatana":
-                return this._connectors.First(c => c is MangaKatana);
-            case "Mangasee":
-                return this._connectors.First(c => c is Mangasee);
-            case "Mangaworld":
-                return this._connectors.First(c => c is Mangaworld);
-            case "Bato":
-                return this._connectors.First(c => c is Bato);
-            case "Manga4Life":
-                return this._connectors.First(c => c is MangaLife);
-            case "ManhuaPlus":
-                return this._connectors.First(c => c is ManhuaPlus);
-            case "MangaHere":
-                return this._connectors.First(c => c is MangaHere);
-        }
-
-        throw new Exception();
+            "MangaDex" => this._connectors.First(c => c is MangaDex),
+            "Manganato" => this._connectors.First(c => c is Manganato),
+            "MangaKatana" => this._connectors.First(c => c is MangaKatana),
+            "Mangasee" => this._connectors.First(c => c is Mangasee),
+            "Mangaworld" => this._connectors.First(c => c is Mangaworld),
+            "Bato" => this._connectors.First(c => c is Bato),
+            "Manga4Life" => this._connectors.First(c => c is MangaLife),
+            "ManhuaPlus" => this._connectors.First(c => c is ManhuaPlus),
+            "MangaHere" => this._connectors.First(c => c is MangaHere),
+            _ => throw new UnreachableException($"Could not find Connector with name {connectorName}")
+        };
     }
 
     public override bool CanWrite => false;
diff --git a/Tranga/MangaConnectors/MangaDex.cs b/Tranga/MangaConnectors/MangaDex.cs
index 005da07..cbb8ffb 100644
--- a/Tranga/MangaConnectors/MangaDex.cs
+++ b/Tranga/MangaConnectors/MangaDex.cs
@@ -243,7 +243,7 @@ public class MangaDex : MangaConnector
                     continue;
                 }
                 
-                if(chapterNum is not "null")
+                if(chapterNum is not "null" && !chapters.Any(chp => chp.volumeNumber.Equals(volume) && chp.chapterNumber.Equals(chapterNum)))
                     chapters.Add(new Chapter(manga, title, volume, chapterNum, chapterId));
             }
         }
diff --git a/Tranga/Server.cs b/Tranga/Server.cs
index 4e387f1..dbf80a5 100644
--- a/Tranga/Server.cs
+++ b/Tranga/Server.cs
@@ -63,10 +63,11 @@ public class Server : GlobalBase
     {
         HttpListenerRequest request = context.Request;
         HttpListenerResponse response = context.Response;
-        if(request.HttpMethod == "OPTIONS")
-            SendResponse(HttpStatusCode.OK, context.Response);
-        if(request.Url!.LocalPath.Contains("favicon"))
+        if (request.Url!.LocalPath.Contains("favicon"))
+        {
             SendResponse(HttpStatusCode.NoContent, response);
+            return;
+        }
 
         switch (request.HttpMethod)
         {
@@ -79,7 +80,10 @@ public class Server : GlobalBase
             case "DELETE":
                 HandleDelete(request, response);
                 break;
-            default: 
+            case "OPTIONS": 
+                SendResponse(HttpStatusCode.OK, context.Response);
+                break;
+            default:
                 SendResponse(HttpStatusCode.BadRequest, response);
                 break;
         }
@@ -707,14 +711,15 @@ public class Server : GlobalBase
     private void SendResponse(HttpStatusCode statusCode, HttpListenerResponse response, object? content = null)
     {
         //Log($"Response: {statusCode} {content}");
+
         response.StatusCode = (int)statusCode;
         response.AddHeader("Access-Control-Allow-Headers", "Content-Type, Accept, X-Requested-With");
         response.AddHeader("Access-Control-Allow-Methods", "GET, POST, DELETE");
         response.AddHeader("Access-Control-Max-Age", "1728000");
         response.AppendHeader("Access-Control-Allow-Origin", "*");
-
         try
         {
+            
             if (content is not Stream)
             {
                 response.ContentType = "application/json";
@@ -750,7 +755,7 @@ public class Server : GlobalBase
                 stream.Close();
             }
         }
-        catch (HttpListenerException e)
+        catch (Exception e)
         {
             Log(e.ToString());
         }