diff --git a/classes/completion/custom_completion.php b/classes/completion/custom_completion.php
index 99c19e7e..e104c129 100644
--- a/classes/completion/custom_completion.php
+++ b/classes/completion/custom_completion.php
@@ -45,6 +45,10 @@ public function get_state(string $rule): int {
         $report = new mod_studentquiz_report($this->cm->id, $this->userid);
         $userstats = $report->get_user_stats();
 
+        if (!$userstats) {
+            return COMPLETION_INCOMPLETE;
+        }
+
         switch ($rule) {
             case 'completionpoint':
                 $status = $studentquiz->completionpoint <= (int) $userstats->points;
@@ -99,11 +103,15 @@ public function get_sort_order(): array {
      * @param stdClass $course The course containing the StudentQuiz to update.
      * @param stdClass|cm_info $cm The cm for the StudentQuiz to update.
      * @param int|null $userid The user to update state for.
+     * @return bool Status check, true if update_state is triggered.
      */
-    public static function update_state(stdClass $course, $cm, ?int $userid = null): void {
+    public static function update_state(stdClass $course, $cm, ?int $userid = null): bool {
         $completion = new \completion_info($course);
-        if ($completion->is_enabled($cm)) {
+        if ($completion->is_enabled($cm) && $cm->completion != COMPLETION_TRACKING_MANUAL) {
             $completion->update_state($cm, COMPLETION_UNKNOWN, $userid);
+            return true;
         }
+
+        return false;
     }
 }
diff --git a/lang/en/studentquiz.php b/lang/en/studentquiz.php
index ebc1de9e..4a9949d9 100644
--- a/lang/en/studentquiz.php
+++ b/lang/en/studentquiz.php
@@ -82,7 +82,7 @@
 
 $string['completionquestionapproved'] = 'Minimum number of unique approved questions required:';
 $string['completionquestionapprovedgroup'] = 'Require created approved questions';
-$string['completionquestionapprovedgroup_help'] = 'the minimum number of unique questions that a student must author and be approved before the activity is completed. This option can be used with either the Question publishing "Requires approval before publishing" or "Auto-approval" setting, but won\'t be as effective with the latter setting, in case auto-approved questions are later hidden, deleted, or otherwise removed.';
+$string['completionquestionapprovedgroup_help'] = 'The minimum number of unique questions that a student must author and be approved before the activity is completed. This option can be used with either the Question publishing "Requires approval before publishing" or "Auto-approval" setting, but won\'t be as effective with the latter setting, in case auto-approved questions are later hidden, deleted, or otherwise removed.';
 
 $string['completionquestionpublished'] = 'Minimum number of unique authored questions required:';
 $string['completionquestionpublishedgroup'] = 'Require published questions';
diff --git a/tests/custom_completion_test.php b/tests/custom_completion_test.php
index e8207ab2..e7a207ca 100644
--- a/tests/custom_completion_test.php
+++ b/tests/custom_completion_test.php
@@ -69,4 +69,58 @@ public function test_get_custom_rule_descriptions() {
         }
     }
 
+    /**
+     * Test update state function in custom_completion.
+     *
+     * @dataProvider test_update_provider
+     * @covers ::update_state
+     * @param int $completion The completion type: 0 - Do not indicate activity completion,
+     * 1 - Students can manually mark the activity as completed, 2 - Show activity as complete when conditions are met.
+     * @param bool $expected Expected result when run update.
+     */
+    public function test_update_state(int $completion, bool $expected): void {
+        $this->resetAfterTest();
+        global $DB;
+
+        $course = $this->getDataGenerator()->create_course(['enablecompletion' => 1]);
+
+        $user = $this->getDataGenerator()->create_user();
+        $studentrole = $DB->get_record('role', ['shortname' => 'student']);
+        $this->getDataGenerator()->enrol_user($user->id, $course->id, $studentrole->id);
+
+        $studentquiz = $this->getDataGenerator()->create_module('studentquiz', [
+            'course' => $course->id,
+            'completion' => $completion,
+        ]);
+
+        $cm = cm_info::create(get_coursemodule_from_id('studentquiz', $studentquiz->cmid));
+        $completioninfo = new \completion_info($course);
+        $customcompletion = new custom_completion($cm, $user->id, $completioninfo->get_core_completion_state($cm, $user->id));
+        $status = $customcompletion::update_state($course, $cm, $user->id);
+
+        $this->assertEquals($expected, $status);
+    }
+
+    /**
+     * Data provider for test_update_state() test cases.
+     *
+     * @coversNothing
+     * @return array List of data sets (test cases)
+     */
+    public static function test_update_provider(): array {
+        return [
+            'Do not indicate activity completion' => [
+                0,
+                false,
+            ],
+            'Students can manually mark the activity as completed' => [
+                1,
+                false,
+            ],
+            'Show activity as complete when conditions are met' => [
+                2,
+                true,
+            ],
+        ];
+    }
 }