diff --git a/src/main/java/emu/lunarcore/game/service/ChatService.java b/src/main/java/emu/lunarcore/game/service/ChatService.java
index 4521ac5..cdd8d8d 100644
--- a/src/main/java/emu/lunarcore/game/service/ChatService.java
+++ b/src/main/java/emu/lunarcore/game/service/ChatService.java
@@ -24,7 +24,7 @@ public class ChatService extends BaseGameService {
         }
 
         // Get target
-        Player target = getServer().getPlayerByUid(targetUid);
+        Player target = getServer().getOnlinePlayerByUid(targetUid);
 
         if (target == null) {
             return;
@@ -35,7 +35,7 @@ public class ChatService extends BaseGameService {
 
     public void sendPrivChat(Player player, int targetUid, int emote) {
         // Get target
-        Player target = getServer().getPlayerByUid(targetUid);
+        Player target = getServer().getOnlinePlayerByUid(targetUid);
 
         if (target == null) {
             return;
diff --git a/src/main/java/emu/lunarcore/server/game/GameServer.java b/src/main/java/emu/lunarcore/server/game/GameServer.java
index 4e67bd4..cb620fb 100644
--- a/src/main/java/emu/lunarcore/server/game/GameServer.java
+++ b/src/main/java/emu/lunarcore/server/game/GameServer.java
@@ -24,6 +24,7 @@ public class GameServer extends KcpServer {
     private final RegionInfo info;
     private final InetSocketAddress address;
 
+    @Getter
     private final GameServerPacketHandler packetHandler;
     private final Int2ObjectMap<Player> players;
 
@@ -41,7 +42,7 @@ public class GameServer extends KcpServer {
         this.address = new InetSocketAddress(serverConfig.bindAddress, serverConfig.getPort());
         this.packetHandler = new GameServerPacketHandler();
 
-        this.players = Int2ObjectMaps.synchronize(new Int2ObjectOpenHashMap<>());
+        this.players = new Int2ObjectOpenHashMap<>();
 
         // Setup managers
         this.battleService = new BattleService(this);
@@ -58,20 +59,25 @@ public class GameServer extends KcpServer {
         return this.serverConfig;
     }
 
-    public GameServerPacketHandler getPacketHandler() {
-        return this.packetHandler;
-    }
-
     public void registerPlayer(Player player) {
-        players.put(player.getUid(), player);
+        synchronized (this.players) {
+            this.players.put(player.getUid(), player);
+        }
+    }
+    
+    public void deregisterPlayer(Player player) {
+        synchronized (this.players) {
+            Player check = this.players.get(player.getUid());
+            if (check == player) {
+                this.players.remove(player.getUid());
+            }
+        }
     }
 
-    public void deregisterPlayer(int uid) {
-        players.remove(uid);
-    }
-
-    public Player getPlayerByUid(int uid) {
-        return players.get(uid);
+    public Player getOnlinePlayerByUid(int uid) {
+        synchronized (this.players) {
+            return this.players.get(uid);
+        }
     }
 
     public void start() {
@@ -96,6 +102,9 @@ public class GameServer extends KcpServer {
     }
 
     private void onShutdown() {
+        // Close server socket
+        this.stop();
+        
         // Set region info
         this.info.setUp(false);
         this.info.save();
diff --git a/src/main/java/emu/lunarcore/server/game/GameSession.java b/src/main/java/emu/lunarcore/server/game/GameSession.java
index 6fe7e4e..0c6f7b5 100644
--- a/src/main/java/emu/lunarcore/server/game/GameSession.java
+++ b/src/main/java/emu/lunarcore/server/game/GameSession.java
@@ -77,7 +77,7 @@ public class GameSession {
             // Save first
             player.save();
             // Deregister
-            this.getServer().deregisterPlayer(player.getUid());
+            this.getServer().deregisterPlayer(player);
         }
     }
 
diff --git a/src/main/java/emu/lunarcore/server/packet/recv/HandlerPlayerGetTokenCsReq.java b/src/main/java/emu/lunarcore/server/packet/recv/HandlerPlayerGetTokenCsReq.java
index 89962f9..1933431 100644
--- a/src/main/java/emu/lunarcore/server/packet/recv/HandlerPlayerGetTokenCsReq.java
+++ b/src/main/java/emu/lunarcore/server/packet/recv/HandlerPlayerGetTokenCsReq.java
@@ -35,6 +35,12 @@ public class HandlerPlayerGetTokenCsReq extends PacketHandler {
             player = new Player(session);
             LunarRail.getGameDatabase().save(player);
         }
+        
+        // Dont let people log on to the same player at the same time
+        Player prevPlayer = session.getServer().getOnlinePlayerByUid(player.getUid());
+        if (prevPlayer != null) {
+            prevPlayer.getSession().close();
+        }
 
         // Set player object for session
         session.setPlayer(player);