Thanks for getting back to me.
I use Apple Mail.
I have tried training as spam from multiple mailboxes attached to different email addresses.
In the icloud mailbox if I try to train an incoming email as spam, nothing happens. It goes nowhere. No colors change.
The same is true when I try to train incoming mail from the google mail account.
I have email addresses from my business accounts, and there’s an inbox for each of them. So for example email@example.com and firstname.lastname@example.org
For both those accounts, when I try to train as spam, it works. The spam email disappears to whatever it’s supposed to go.
It also seems to be working with messages that come into smart mailboxes.
So the primary problem is that the two email addresses that get the most traffic (and spam) are the ones where training as spam does nothing.
Finally: I came to the forum to see if other people might be having the same problem, and I found a couple right away (training as good works, training as spam doesn’t). In both cases I read about (and forgive me, but I can’t find the discussion threads right now) someone said that there was a known bug, but it was fixed in the most recent beta. The person suggested signing up for the betas (with the usual warnings) to see if that would solve the problem.
And it did solve the problem, but the next day the same problem as back, for the iCloud and Google mail accounts.
Any suggestions much appreciated.