Hello
I’m struggling since yesterday and can’t find a solution to my problem, so I hope you will be able to help me.
Yesterday, we did some electricity work on the house and we had to cut the main line for several minutes. The Raspberry Pi hosting Home Assistant and Zigbee2MQTT was still powered by a UPS, as was the ZigBee coordinator I’m using but as you wan imagine, most of the ZigBee non battery powered devices were off during that time. After we restored power in the house, I noticed several devices were missing.
At first, I thought it was the time needed to establish a ZigBee connection again. But then, I noticed these devices were all up and good to go inside Z2M, but not showed at all inside Home Assistant. I’m using the standard mosquito broker module installed with the supervisor and it was missing many devices, as if they were not sent by Z2M.
I tried many things : when changing the name of the device inside Z2M, it appears inside HA, but with no entity. I tried deleting and then re-adding the device, no luck. I even tried to restore the latest backup, to see if something was corrupted during the power out, but I still had the exact issue. Interestingly, I think, the same devices were not showing inside HA after restoring the backup, letting me to believe I have a real issue somewhere.
Problem is, I can’t find any relevant logs anywhere. What I can notice is many weird (and annoying) behaviors on the ZigBee devices that remained connected in HA after the blackout. For instance, my energy meter is a ZLinky_TIC by LiXee that feeds the energy dashboard and since then, it reports as if I am using an immense quantity of electricity every hour. It seems some part of the whole history of consumption is pushed every hour now.
Among other weird things, many ZigBee devices that still worked lost their room assignment in Home Assistant. I had to changed it manually.
Other than that, I don’t know what is causing this but since I rely heavily on ZigBee now, it’s a big problem for me. So any help towards the right direction would be much appreciated. 
EDIT : I was wrong, the missing devices appear inside Z2M but not HA in MQTT Explorer.
What’s even weirder for me, is that it seems MQTT has the right informations. At least, when I use MQTT Explorer, I can see the devices missing inside Home Assistant, with all the correct informations.
So I’m really lost here : if a device is showing inside Z2M and in MQTT Explorer, how can it be totally absent from HA ? I can’t find it anywhere…