diff --git a/src/Form/ExtlinkAdminSettingsForm.php b/src/Form/ExtlinkAdminSettingsForm.php
index 46a677f..24bc2c8 100644
--- a/src/Form/ExtlinkAdminSettingsForm.php
+++ b/src/Form/ExtlinkAdminSettingsForm.php
@@ -187,7 +187,7 @@ class ExtlinkAdminSettingsForm extends ConfigFormBase {
       ->set('extlink_css_explicit', $values['extlink_css_explicit'])
       ->save();
 
-    parent::SubmitForm($form, $form_state);
+    parent::submitForm($form, $form_state);
   }
 
   /**