For the past couple of days, my POWR2 sensors haven’t been updating in Home Assistant. If I open the app on my phone, the sensors start updating again and also resume updating in Home Assistant.
However, once I close the app, they stop updating in Home Assistant again.
The same behavior happens on the Sonoff website (https://web.ewelink.cc/) as well.
How can I fix this? They’ve always worked perfectly until now.
I think I experienced a similar issue with my POWR2s quite a while ago.
This led me to flash them with ESPHome and I have not had any issues since.
quite a drastic solution.
but… do you have a tutorial to install esp home on POWR2?
and, the measurements are more precise than the stock firmware?
Drastic, indeed - but well worth it 
There must be tutorials out there, I wouldn’t habe been able to do it otherwise, but I don’t have the one I used at hand.
I might have actually used the same (or at least a very similar) process to flashing 15 of my S31s with ESPHome - honestly, it’s too long ago for me to remember.
And I probably used the info on the ESPHome site as a starting point for the code:
Sonoff POWR2 | devices.esphome.io
If you don’t have the kit to flash yet, in addition to the TTL Serial Converter Adapter, I bought a set of these:
Goupchn Test Hooks to Breadboard Female Jumper Wires Soft Flexible Silicone Test Leads for Electrical Testing: Amazon.com: Industrial & Scientific
Very useful!
Re. the precision: it seems to be in line with e.g. a Kill-A-Watt Device, but I don’t really have a calibrated device to compare it to.
Check your connection to the Sonoff servers. If you have it blocked/firewalled this is what happens. No matter if you use something like SonoffLAN: Whenever these devices can’t reach their mothership they stop updating their state to HA.
Thanks! I’ll keep that in mind next time it freezes again. For now, it’s working again without me doing anything.