There’s been some discussion about the new health check “feature” letting you know about devices that have gone offline. Depending on what the device is, the easiest fix is to remove the battery for about 15 seconds and then replace it. By doing so, hopefully the device will wake up and reconnect again. Sometimes you have to do a full reset and re-pair it to the hub. Although one member did comment that the app just hasn’t updated the status and by somehow interacting with it will bring it back. As far as the help topic link goes, it doesn’t work for me either.