diff --git a/Modules/LearningModule/classes/class.ilHelpMappingTableGUI.php b/Modules/LearningModule/classes/class.ilHelpMappingTableGUI.php
index 1e25a4b5dce5..ffb695c0bfb6 100644
--- a/Modules/LearningModule/classes/class.ilHelpMappingTableGUI.php
+++ b/Modules/LearningModule/classes/class.ilHelpMappingTableGUI.php
@@ -63,7 +63,7 @@ public function __construct(
     public function getChapters(): void
     {
         $hc = ilSession::get("help_chap");
-        $lm_tree = $this->parent_obj->object->getTree();
+        $lm_tree = $this->parent_obj->getObject()->getTree();
 
         if ($hc > 0 && $lm_tree->isInTree($hc)) {
             //$node = $lm_tree->getNodeData($hc);