Several Matter devices became unavailable and will not reconnect

I have encountered a strange issue that I cannot seem to find a solution to.

This might not be related, but a couple weeks ago, I was affected by Hurricane Helene and lost power for several days. There were some power flickers before the power went off, but I do not think they were surges that would lead to device damage. Once power was restored, I noticed several of my HA devices were no longer working correctly.

The main devices I have trouble with are a couple of my Nanoleaf bulbs (which are thread enabled), 1 Nanoleaf Bulb that is Matter connected, 1 random Wifi LED bulb, a Govee Matter LED strip, and 2 Aquara FP-2.

During my troubleshooting process, I updated Apple Homepod Mini’s to iOS 18 but that did not help.

I could Ping most of the devices in HA just fine. The Matter devices were accessible in Apple Home

I tried removing the devices from HA and repairing them via Matter from the Apple Home app, but they fail to connect.

All my HA integrations are up to date. Does anyone have any advice?

Is the Homepod Mini your only Thread border router? Or do you have additional Homepods or AppleTV? Are you also running another border router, e.g. a SkyConnect dongle in Home Assistant with the Open Thread Border Router addon? There currently are issues when using multiple border routers, especially when mixing Apple and OTBR.

Also, do you have a iPhone/iPad you could install the Eve app on? It can show the thread status of all devices, including which other devices they are connected to. It’s not a visualisation, but at least a list and you might be able to identify the issue.

There are 4 homepod mini’s and a Apple TV 4k. The Thread network in HA was provisioned from the Apple Home app. I do not use the OTBR addon.

I have also setup several BLE Proxy devices throughout the house to handle the bluetooth connections.

I do own a few Eve devices and have been using the app to see the network. The devices that do not connect also do not show up.

I took the Govee LED strip and reset several times trying to connect it first to Apple Home then use a Matter Pairing code to connect it to HA, and also trying to pair directly to HA.

While it pairs fine to Apple Home, I never can get it to connect to HA.

Please check if this issue Matter over Thread Devices unavailable - Home Assistant Only · Issue #123835 · home-assistant/core · GitHub might be related. If yes, try to answer all questions listed in this comment by marcelveldt:
Matter over Thread Devices unavailable - Home Assistant Only · Issue #123835 · home-assistant/core · GitHub