Azure - Receiving EmailDeliveryReportReceived but not EmailEngagementTrackingReportReceived

Question

I have both events selected in my Event Subscription.

But for some reason, only the EmailDeliveryReportReceived is being posted to my endpoint. I've actually clicked and opened the email on my phone. Anyone know why?

  app.post("/events", authExpress, (req, res) => {
    console.log("============ Event hook ===================");
    console.log(`${JSON.stringify(req.body)}`)
    const eventList: Event[] = req.body;
    eventList.forEach((event) => {
      updateEmailLog(event);
    });

    res.status(200).send("success");
  });