We are using Journey Builder to send out transactional emails. I am reviewing one of these journeys and I can see that the email activity has a small number of "Not Sent", which I assume means they entered the journey and marketing cloud decided not to send to them for some reason.
The email activity uses a Transactional send classification (since it is a transactional email), which as I understand ignores subscription status, so I'm guessing it's not that.
Is there a way that I can find out why they were not sent? I couldn't find anything in the documentation about what this actually means.
[edit] just wanted to add that while it is possible to click on some of the numbers and percentages to drill down, the Not Sent number is not clickable.
Thanks