Not looking for solutions per se, just curious about what's going on. A bit of back story, I work out of state and am gone for 2-3 weeks at a time. Seems like every time I come home I find changes with my system.

A couple months ago, I successfully connected a Tapo P125M switch and a generic Matter light bulb I got from Amazon via Matter. I only had on/off control of the bulb, but still it was Matter progress. Both Matter devices worked perfectly via UD Mobile.

At that time I also had Apple Home installed, but no Apple hubs/bridges. In Home, Home settings, the EISY showed up under Home Hubs & Bridges.

I'm also playing with GE Cync color bulbs and GE Cync plugs that I picked up super cheap at a discount warehouse. These Cync devices are not Matter compatible. However, while using them, when I looked at the devices connection path, and at least one Cync device would show as connected to the EISY via Bluetooth even though I couldn't add/control the Cync devices with EISY/UD Mobile.

Current state: I came home last week and discovered neither matter device was connected. I tried rebooting the EISY, syncing UD Mobile and finally removing and re-adding the matter devices. I have not been able to re-add the matter devices as matter devices. I gave up on the cheap Amazon bulb and used the Kasa plugin to re-add the Tapo P125M plugs. I personally have made no changes to EISY or UD Mobile configurations from when the Matter devices worked to not working. EISY may have updated while I was gone, and fairly certain there was a UD Mobile for iOs update as well.

Also I noticed, EISY does not show up as a Hub/Bridge in Apple Home anymore and none of the Cync devices are using EISY as a connection point anymore.

I tried adding a new Tapo P125M as a matter device and got as far as being asked to assign a name to the new plug. While typing in the name, UD Mobile screen turned grey in the background and an error msg popped up. When I clicked next after entering a device name, the entire processed failed and I was never able to get that far again.

I have now added an 2nd gen Apple Home Pod, which shows up as a Hub/Bridge in Apple Home, but I still can't add Matter devices.

Anywho, I know Matter is still in development and that I am mostly clueless and my issues could be self inflicted. Just seemed like there had been a giant leap in Matter functionality and then a big step backwards.

If you made it this far, thanks, and if you have any suggestions or insights, I would greatly appreciate it. Please don't suggest I give up on Matter. Now that I know it exists, I have to keep poking at it. I'm the guy that has the overwhelming compulsion to press the big red button that says "Do not push this button" 🙂

Matter is still "new" and compatibility is at various stages between products and platforms. You might have seen my forum thread about recent experiments I've done with it, after a first round last spring. All my Matter devices are in test conditions, none in regular use. UDI is still listing Matter as being in beta.

Directly adding a new Matter device to the eisy most often fails. I've had the best results by first adding (commissioning) a new device to Google Home, then creating a share pin code, and using that to add it to the eisy. I've added a Matter Cync bulb, Cync outlet module, Nanoleaf (Thread) bulb this way. Also shared Hue bulbs as Matter devices to the eisy.

To add back a Matter device that had already been configured, you need to factory reset it first. For bulbs this usually means turning it on and off several times, often 5 times or so.