/**
  * @param Member $member
  * @param Channel $channel
  * @param Campaign $campaign
  * @return Member
  */
 protected function findExistingMember(Member $member, Channel $channel, Campaign $campaign)
 {
     $searchCondition = ['channel' => $channel, 'subscribersList' => $campaign->getSubscribersList()];
     if ($originId = $member->getOriginId()) {
         $searchCondition['originId'] = $originId;
     } else {
         $searchCondition['email'] = $member->getEmail();
     }
     return $this->findEntityByIdentityValues(ClassUtils::getClass($member), $searchCondition);
 }