diff --git a/Classes/Service/MailTemplateService.php b/Classes/Service/MailTemplateService.php
index 224f1794718fea74a49da69a09547c084ccc2de9..ada7cca2b3bc2148364ec71f548b5dcce735f1de 100644
--- a/Classes/Service/MailTemplateService.php
+++ b/Classes/Service/MailTemplateService.php
@@ -925,7 +925,7 @@ class MailTemplateService {
 				$allMarker .= $key . ': ' . $value . PHP_EOL;
 			} elseif (\is_array($value)) {
 				foreach ($value as $innerKey => $innerValue) {
-					$allMarker .= $innerKey . ': ' . $innerValue . PHP_EOL;
+					$allMarker .= $key . '.' . $innerKey . ': ' . $innerValue . PHP_EOL;
 				}
 			} elseif (\is_bool($value)) {
 				$valueAsString = $value ? 'true' : 'false';