debugging rsvp-submit.php

static/rsvp-submit.php

@@ -204,6 +204,7 @@ EOD;
 
     error_log('RSVP mail error: ' . $mail->ErrorInfo);
 
-    http_response_code(500);
-    echo 'An error occurred while sending the RSVP.';
+    echo '<pre>';
+    echo htmlspecialchars($mail->ErrorInfo);
+    echo '</pre>';
 }