VeSync device controls unavailable, but sensors work

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1

I reconnected a couple of old VeSync switches for the summer season that hadn’t been used over the winter. The reconnected devices all showed up in the VeSync app. One of the other switch’s controls that had been used by HA all along (not disconnected for the winter) now has gone unavailable. Weirdly, the sensors are available for the switch, just not the controls.

Reloading the service and running the “update devices” service did nothing. I also tried removing and re-adding the device from the Vesync app.

Anyone ever see something like this?

2

This was fairly time-consuming to resolve; after trying many options I ended up having to to a hard reset per the manual:

Press and hold the power button for about 15 seconds until the indicator light blinks blue rapidly (4 times a second). The indicator light will blink rapidly 10 times, and the smart outlet will turn off.

If I remember right, this has to be done from the powered-off state, not mentioned in the instructions.