Help with 'device has not reported back for x time period'

I can’t find out what’s the trigger of that “device hasn’t reported in x hrs” card.
I got notifications about sensors which were active every x hours, while they should’ve been quiet for the last 24h…

This flow might be interesting, it shows sensor devices (pir/temperature/contact), which didn’t send any update for 24h, and the other ones with a timestamp (if wanted with date & time).
The script used was made by Robert Klep.