diff --git a/report.php b/report.php
index f288027..5a36221 100644
--- a/report.php
+++ b/report.php
@@ -24,7 +24,6 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-require_once($CFG->dirroot . '/mod/quiz/report/attemptsreport.php');
 require_once($CFG->dirroot . '/mod/quiz/report/statistics/report.php');
 require_once($CFG->dirroot . '/question/type/stack/locallib.php');
 
@@ -35,7 +34,7 @@
  * @copyright 2012 the University of Birmingham
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-class quiz_stack_report extends quiz_attempts_report {
+class quiz_stack_report extends \mod_quiz\local\reports\attempts_report {
 
     /** @var The quiz context. */
     protected $context;
diff --git a/version.php b/version.php
index 86fc54f..01cbfd6 100644
--- a/version.php
+++ b/version.php
@@ -25,7 +25,7 @@
 defined('MOODLE_INTERNAL') || die();
 
 $plugin->version   = 2014111200;
-$plugin->requires  = 2013101800;
+$plugin->requires  = 2023042400;
 $plugin->cron      = 0;
 $plugin->component = 'quiz_stack';
 $plugin->maturity  = MATURITY_STABLE;