I should also say that it’s certainly true that there can be issues with Wi-Fi drowning out zigbee, but that’s not usually the problem that fits the symptoms you’re describing. In those cases, you wouldn’t be able to control the device from the app either.
Z wave and wifi don’t interfere with each other, so you don’t have to worry about that.
But WiFi can drown out nearby zigbee, particularly boosted Wi-Fi.
At my house, we have a Wi-Fi booster. If we plug it in on the north wall in one room, all the smartthings – controlled zigbee devices to the west of it drop off-line. If we just move the Wi-Fi booster to the east wall, all the zigbee devices work fine.
So the first step is to make sure that your SmartThings hub is at least 3 m away from your Wi-Fi router or any access point.
But sometimes the problem is bigger than that, and your Wi-Fi router is broadcasting on a channel which is just drowning out your zigbee devices.
You do have the option to change your Wi-Fi router, typically between channels 1, 6, and 11, so what’s the best Wi-F…