diff --git a/src/Form/WebformHandlerFormBase.php b/src/Form/WebformHandlerFormBase.php
index be344a8..98078b4 100644
--- a/src/Form/WebformHandlerFormBase.php
+++ b/src/Form/WebformHandlerFormBase.php
@@ -189,6 +189,11 @@ public function submitForm(array &$form, FormStateInterface $form_state) {
     if ($is_new) {
       $this->webform->addWebformHandler($this->webformHandler->getConfiguration());
     }
+    else { // Update an existing handlers config.
+      $id = $this->webformHandler->getHandlerId();
+      $currentConfig = $this->webformHandler->getConfiguration();
+      $this->webform->getHandlers()->setInstanceConfiguration($id, $currentConfig);
+    }
     $this->webform->save();
 
     // Display status message.