message: check api_response.mid and api_response.message_id for a value to match mid
diff: @@ -24,7 +24,8 @@ function Facebookbot(configuration) {
  if (convo) {
  for (var s = 0; s < convo.sent.length; s++) {
  if (convo.sent[s].sent_timestamp <= message.delivery.watermark ||
  - (convo.sent[s].api_response && convo.sent[s].api_response.mid == mid)) {
  + (convo.sent[s].api_response &&
  + (convo.sent[s].api_response.mid || convo.sent[s].api_response.message_id) == mid)) {
  convo.sent[s].delivered = true;
  }
  }
  