diff --git a/classes/local/tool_dynamic_cohorts/condition/cohort_field.php b/classes/local/tool_dynamic_cohorts/condition/cohort_field.php
index 239cd4e..f34a390 100644
--- a/classes/local/tool_dynamic_cohorts/condition/cohort_field.php
+++ b/classes/local/tool_dynamic_cohorts/condition/cohort_field.php
@@ -491,7 +491,6 @@ public function get_sql(): condition_sql {
      */
     public function get_events(): array {
         return [
-            '\core\event\cohort_updated',
             '\core\event\cohort_member_added',
             '\core\event\cohort_member_removed',
         ];
diff --git a/classes/observer.php b/classes/observer.php
index 5b6692c..161555b 100644
--- a/classes/observer.php
+++ b/classes/observer.php
@@ -17,7 +17,6 @@
 namespace tool_dynamic_cohorts;
 
 use core\event\base;
-use tool_dynamic_cohorts\rule_manager;
 
 /**
  * Event observer class.
@@ -50,7 +49,7 @@ public static function process_event(base $event): void {
     protected static function get_userid_from_event(base $event): int {
         $data = $event->get_data();
 
-        if (array_key_exists('relateduserid', $data)) {
+        if (array_key_exists('relateduserid', $data) && !empty($data['relateduserid'])) {
             $userid = $data['relateduserid'];
         } else {
             $userid = $data['userid'];