For Zigbee devices I’m using this script - A script to check sensor last update - #39 by Sharkys
The behavior you described above just happened to me after I replaced + changed position of two Zigbee routers and get rid of one router - I was expecting problems, during next 2 days (not immediately), I had to do maintenance of 6 Zigbee sensors - luckily script notified me automatically.
So don’t you have some Zigbee router / light for example, you are turning off from power ? Or have you recently changed any of your Zigbee routers ? Eg. plugs etc ?
And also as Peter mentioned, I had issues with Tradfri power socket…6 months ago I moved them to Zigbee2MQTT and Homey Zigbee network improved. So not only Ikea lights for me.
