The device can only be turn on and cannot be turn off?
The device can only be turn on and cannot be turn off
If your device is a low-power device such as a sensor, it cannot be turned off. If you do not need it to continue working, remove it from the app or completely power off the device. If it's not a low-power device, restore the device to factory settings and add it again. Then check whether you can turn it off in the app. If you still cannot turn it off, use the physical button and check whether you can turn it off. If you cannot turn it off with the physical button, contact the manufacturer to check the hardware.
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