[TASK] Fixing exxtension keyin language identifier

Classes/Service/MailTemplateService.php

@@ -204,7 +204,7 @@ class MailTemplateService {
 	 * @return array
 	 */
 	public static function getDefaultTemplateMarker($translationKey, array $marker, $extensionKey = 'sg_mail') {
-		$languagePath = 'LLL:EXT:sg_register/Resources/Private/Language/locallang.xlf:' . $translationKey;
+		$languagePath = 'LLL:EXT:' . $extensionKey . '/Resources/Private/Language/locallang.xlf:' . $translationKey;
 
 		// Need the key for translations
 		if (trim($extensionKey) === '') {