src/de/steamwar/bungeecore/comms/handlers/InventoryCallbackHandler.java

@@ -44,6 +44,7 @@ public class InventoryCallbackHandler implements SpigotHandler {
             if(type == CallbackType.CLICK) {
                 new CloseInventoryPacket(owner.getId()).send(ProxyServer.getInstance().getPlayer(owner.getUuid()));
             }
+            return;
         }
         if(type == CallbackType.CLICK) {
             int pos = byteArrayDataInput.readInt();