Connectivity Issues

My smart home is fairly simplistic though I do have quite a few devices. The architecture I have I have worked to limit the brands and types of devices to limit complexity. In my home I have a few Wemo switches, a large number of Hue Bulbs (61) and some Samsung branded sensors (1 motion, several multipurpose, and 3 plugs spread around the house as repeaters. All of these devices are connected to SmartThings which is then connected to Google Home for voice activation. The layout of my house is 3 stories, total of about 5500 square feet. That includes an unfinished basement which is were my data closet is. The majority of my sensors are on the 2nd floor of the house so I have 2 plugs on the 1st floor as repeaters to get upstairs and 1 upstairs.

This has worked great. My light automations were triggered by the sensors just fine till about the middle of December. That’s when I started seeing some delay in how things worked. For instance, a door would open and the lights wouldn’t come on, so I’d close the door and reopen and then the lights would come on. The problems like this have over the last 3 weeks become more and more prevalent and worse where now automation isn’t happening at all for many of my sensors. I finally went into the classic app and noticed that 2 of my plugs (the ones on the first floor) are showing unavailable. On top of that, many of my sensors on the second floor also show unavailable. Based on previous advice on this forum I bought the plugs because I was seeing problems with devices constantly not working and I was told my network wasn’t strong enough to maintain what I was doing. Getting the plugs fixed that problem for about the last year just fine.

So, what is the problem here? Unplugging and re-plugging the plugs back in don’t seem to be fixing anything. Changing the batteries on the sensors isn’t helping either. I’m now seeing that my hue bulbs are not showing active as well in the app. In the Hue app they are working fine and I can control them just fine from that app. Voice activation though through Google is not working for the devices which are showing unavailable in ST. I have unplugged the hub for 5 minutes and plugged it back in.

Based on normal troubleshooting methodology, I can control the lights at the source, but not once they are in ST. Any thoughts?

I too am seeing odd devices becoming disconnected, and from what appears to be a similar time frame, my system was also very stable until late last month

For no apparent/odvious reason random devices have just stopped working

Our 2 issues may not be linked but your disconnection issues do appear to be similar to mine

JD recommends popping a mail over to support to see if they can help, might be worth you doing the same