src/main/java/com/lishid/openinv/listeners/OpenInvPlayerListener.java

@@ -77,10 +77,15 @@ public class OpenInvPlayerListener implements Listener {
             }.runTaskLater(plugin, 1);
         }
 
-        SpecialEnderChest enderChest = OpenInv.enderChests.get(player.getUniqueId());
+        final SpecialEnderChest enderChest = OpenInv.enderChests.get(player.getUniqueId());
         if (enderChest != null) {
+            new BukkitRunnable() {
+                @Override
+                public void run() {
                     enderChest.playerOffline();
                 }
+            }.runTaskLater(plugin, 1);
+        }
     }
 
     @EventHandler