Data Activator Not Activating

Thanks for all your replies. I've tried all suggestions and followed instructions/guidance on every link and am still not getting anywhere.

Oddly, I did receive an alert that was obviously triggered by some changes I'd made, but it was only 1 and correlated with only a single time I'd changed things to hit the trigger. I received it about 3 hours after I'd made the change and I did nothing differently, but this time it took for some reason. I couldn't get it to happen again.

I can see on the Reflex that it's registering the changes (a nice little line graph dipping and rising), but nothing seems to be triggering (except for that one time for reasons best known to PBI).

My main problem is that the whole process isn't intuitive, so fault finding just confuses me. Setting the alert up seems straightforward enough, but when it doesn't work...it just doesn't. I could do with a simple summary (written in crayon if possible) explaining exactly what I've set up. At least PowerAutomate has the good grace to say 'Hey, it didn't run'.

I'll keep trying.