I also have the same issue… it doesn’t seem to be related to one specific device/communication protocol type… as far as I know all my devices were working at 9:25 am today (1/3/2026) and then shortly after that a vast majority of my devices no longer work. I had turned on a few switches at that time and then about 30 mins or so later thoes same devices no longer respond. Most devices are zigbee or zwave, but even some of my matter devices are not working. A few devices on wifi (tp-link & Wiz) still work from smartthings, and my matter connection to my Nest Thermostat still work, but not the matter connection to a couple outlets, and switches. Alexa control of my Hue lights still work, but i cannot turn on the hue bulbs via smartthings. This is not just 3rd party devices, “OEM” smartthings outlets & buttons also do not work (pressing them does not show any activity in the app). Trying to turn on a smartthings outlet via the app eventually produces the error “a network or server error occurred. Try again later”. I have restarted my home network, and removed the batteries and power from my V2 hub, none of these items fixed the issue. My internet is working (as I am writing this from my home computer in the dark … because none of the lights will turn on). @SmartThings HELP!!!