code: public function setAsUnsubscribed(\DateTime $unsubscriptionDate, $unsubscriptionIp = '127.0.0.1')
      {
          $this->subscriptionStatus = self::STATUS_UNSUBSCRIBED;
          $this->unsubscriptionDate = $unsubscriptionDate;
          $this->unsubscriptionIp   = $unsubscriptionIp;
  
          return $this;
      }
docs: Set this recipient as unsubscribed
  @param \DateTime $unsubscriptionDate The recipient unsubscription date
  @param string    $unsubscriptionIp The recipient unsubscription Ip
  
  @return $this