The air gap does seem to work, so that’s good to know for next time it happens.
One of the two switches I have is controlling a light fixture with three 60W equivalent Philips LED dimmer bulbs. The other is controlling a fixture with five IKEA dimmable LEDs. I don’t recall the exact type/model for either one.
There is also this thread: Switch completely frozen - #2 by thetech101
Which I think is the same as what you are experiencing. And I’m also worried about how long I can keep my wife from noticing and making me put back in the dumb switch! 
I have the older gen 1 dimmer and am also experiencing the same thing, so seems to not be specific to Gen 1 or Gen 2.
Seth
Are the dimmers grounded? It’s strange that it’s happening on two different circuits with different generation switches. Maybe a voltage surge or leak somewhere? Maybe even a wonky GFCI on the same circuit?
I had a similar issue at first but turned out I wasn’t using the right device handler. Changing to the correct one fixed my issues.
Im having the same issue with one of my switches. What are you guys talking about when you say the air gap works?
There’s a little piece of plastic at the bottom of the switch that you can pull forward (out towards you away from the wall) which cuts power to the switch. When you push it back in, the switch resets and usually works again.
Unfortunately it doesn’t solve the problem permanently. My switch gets stuck like this at least once a week which is annoying – enough that I’ve only kept the one in my own bathroom, as my wife would NOT put up with a simple light switch that stops working once a week.
I’m echoing the concerns here and have a very similar issue. I’ll repost what I mentioned on @BertABCD1234 's thread above:
Just checking back in a few months later to note that this issue never resolved itself – the switch goes dead at least once a day and will be getting swapped out soon for a GE Switch. A light switch that can’t switch the light can’t stay any longer.
I haven’t – looks like that’s more complicated than just going into the device settings in smartthings, if these are the right instructions: https://support.inovelli.com/portal/kb/articles/how-to-s-general-how-to-update-firmware-z-stick-z-wave-pc-controller
Not super interested in buying a $35 zwave stick to fix a $30 lightswitch.
Correct, those are the correct instructions. It’s another expense, but until SmartThings allows/programs OTA updates, it’s a necessary…Fortunately, for us Hubitat users, there is an alternative other than buying a Z Wave USB.
I found one of the sticks on eBay for cheaper, so I’ll give that a try, but it’s super frustrating that this is even necessary. It’s a light switch. I get that the “smart” functions are subject to lots of complicated software interactions, but on/off by itself should not ever fail.
I don’t know if anyone has followed those firmware update instructions lately but they are not as foolproof/easy as advertised. The software required is not intuitive to find (the provided link is not current), the interface is different, and the OTA update never went through. “Should take 5-10 minutes” – I gave up after it was processing for 30.
So… unfortunately I think I’m still going to have to swap the switch out for something else. :-/
Shoot me a PM, let’s see if swapping out the switch will fix your issue. I’ll flash the new firmware on the one we send out to you. Apologies for the issues, we’re trying to figure this out as well.
@thenrich -How far away from the hub is the light switch? I flashed two dinners in a mere 5 mins total, but I moved the Z stick right next to it.
The hub itself is down a floor, but there are a few other z-wave repeaters between the two. I bought an Aeotec z-wave stick to do the firmware update process and have that plugged into a laptop a foot away from the switch.
Sent!
This just happened to me too. One of my LZW31-SN froze up completely. Same as reported here and the other thread (no response from local buttons nor from Zwave/SmartThings). Rebooting via Airgap brought it back to life.
What I wanted to add here is that I had not seen this until today. Just yesterday I went through my whole house updating ALL my Inovelli Red switches to .otz Firmware 1.44 and .bin 1.39. I should also add while going through this process I used the ST Classic app to re-include the switches with S0 security. Previously there were all using S2 (via the ST New app)
So far I’ve only seen it one time on one switch. Will report back if it recurs. But it doesn’t appear to be resolved with the latest firmware (1.44.otz and 1.39.bin as of yesterday)
Update: the replacement switch Inovelli sent me works! Had to fiddle with the settings a bit to get the ramp rates back to normal (for a while it seemed like everything except the ON command worked) but so far so good.