Definitely check the user profiles whether those categories are in the “Muted” set.
I had that happen to me last week or so. Wasn’t receiving emails from certain categories that I am certain I should, but receiving emails from others. Turns out that a few categories have been put into “Mute” for some reason.
Deleting those mutes made everything work again. I then manually scanned through my users list and found several user accounts having similar muted categories. I am pretty sure the users themselves (who are not power users) did NOT put them in.
Yeah that’s odd - but this is only two users that have been created recently and they’re both only watching one category with this in the muted bit for each user that has the problem.
In the process of trying this out, I find that in he latest version beta11, watch/track/mute categories can no longer be set!
The UI still works fine. Pressing Save still sends the correct REST PUT command with the correct list of categories. The response JSON always comes back with the original, unchanged list.