Tasmotized Sonoff POW R2 resets counter itself?

Hi there,

curious if anyone else has experienced similar:

I have 5 POW R2 in place (tasmotized). For no obvious reason, two of them have last night reset total consumption counter.
Looking in HA database where sensor values are being reported and found this.

So, from total value of 1.162, in the next iteration it was unknown to report, and next one, a minute later reported only 0.362
once again, I did not reset counter myself. Neither reset POW device back to factory values or whatever.
Both devices were in use by linked home appliances (e.g. dishwasher was on) .
Indeed, there was some power interrupt around that time but it shold not affect POW as it writes readings in its flash memory?

Anyone with a clue why this happens?
Should I eventually link it to the bug in tasmota? in taht case it makes device quite unreliable.

Thanks guys.