Mailjet not send the template language part in the message

Question

I am using mailjet to send notification to user if they upload a file. So I created a template like that

But when i got the message it only send the title and first description part, it does not send the template language part.

I dont know if I send the request wrongly. That is how I implemented the request

 async sendNotificationMail() {
    try {
      await this.mailClient.sendMail({
        to: 'mehmet.sayin@steiner.ch',
        template: '4714581',
        AdvanceErrorHandling: true,
        variables: {
          userName: 'Mehmet',
          projectName: 'Test Project',
          senderName: 'Mehmet',
          senderEmail: 'sayinmehmet47@gmail.ch',
        },
      });
    } catch (error) {
      this.logger.error(error);
    }
  }

am I need to activate sth to show also template language part? I also tried it with ** TemplateLanguage: true, ** but does not show that part.