I did restart the phone it's the first thing I try (this is what fixes location based focus modes which have become unreliable in 18.x for me).
I also have a couple of simple automations that change the mode to light whenever I open Maps, and back to dark when I close it (I use dark mode systemwide, but dislike the dark mode Maps look), and these still work the way I want them, without confirmation.
So I tried timed automation (for the same coffee machine shortcut), and here's where it gets interesting. If the phone is unlocked, it works as it should, no confirmation, just turns the machine on at the set time. Same if the phone is locked, but the display is awake (tapped or picked up, but not unlocked). But the phone is locked with the screen off (I don't use always-on display, even though the 15Pro supports it), the timed automation just fails silently, no confirmation dialog, just does not run.
So it appears that the issue is with the automations that run when the phone is locked with the screen off. This is new in 18.2 for me.
I suspect some new half-cooked security 'feature' from Apple. There are all kinds of warnings about automations being enabled that are impossible to turn off, they clearly consider them a security risk and deal with it in a way that is typical of current Apple - by making them harder to use and less useful.