public function replacePlaceholdersInStartedCombinedMail(ClientSurvey $client_survey, EmailType $type, string $template, string $lang): array|string 	{ 		$email_template = __('email-templates.survey-started-combined-mail-default-template-with-placeholders'); 		$survey_email_template = $client_survey->emailTemplates()->where('type', $type->value)->first();  		if ($survey_email_template) { 			return $template; 		}  		$date = $this->getSurveyStartDate($client_survey); 		$template_part_two_optional = str_replace(':date', $date, __('email-templates.survey-started-online-mail-default-template-part-two-optional', [], $lang));  		return str_replace(':part_two_optional', $template_part_two_optional, $email_template); 	}