diff --git a/core/modules/contact/src/MessageForm.php b/core/modules/contact/src/MessageForm.php
index 1de2b8e..a6976f9 100644
--- a/core/modules/contact/src/MessageForm.php
+++ b/core/modules/contact/src/MessageForm.php
@@ -217,9 +217,8 @@ public function save(array $form, FormStateInterface $form_state) {
     if ($message_results[MailHandler::MESSAGE_RECIPIENT]['result']) {
       drupal_set_message($this->t('Your message has been sent.'));
     }
-    else {
-      drupal_set_message($this->t('Your message has not been sent.'), 'error');
-    }
+    // \Drupal\Core\Mail\MailManager will display an error message, if the
+    // message couldn't be sent.
 
     if (isset($message_results[MailHandler::MESSAGE_COPY])) {
       if (!$message_results[MailHandler::MESSAGE_COPY]['result']) {