diff --git a/CommonCore b/CommonCore
index 0c68dfd..746ae70 160000
--- a/CommonCore
+++ b/CommonCore
@@ -1 +1 @@
-Subproject commit 0c68dfd19dc32a848be2cf399e00bc2863739b57
+Subproject commit 746ae701d8abf1534de14b57ae650ac76e9c4d9d
diff --git a/src/de/steamwar/bungeecore/commands/CalendarCommand.java b/src/de/steamwar/bungeecore/commands/CalendarCommand.java
index 45bf05b..488ae1b 100644
--- a/src/de/steamwar/bungeecore/commands/CalendarCommand.java
+++ b/src/de/steamwar/bungeecore/commands/CalendarCommand.java
@@ -92,6 +92,7 @@ public class CalendarCommand extends SWCommand {
                 if (b) return;
                 if (month != Month.DECEMBER) return;
                 if (present.getKey() != day) return;
+                if (NodeMember.getNodeMember(present.getValue(), user.getId()) != null) return;
                 NodeMember.createNodeMember(present.getValue(), user.getId());
                 Message.send("ADVENT_CALENDAR_OPEN", player, SchematicNode.getSchematicNode(present.getValue()).getName());
             });