AG One v9 won’t turn off the led bar in any of the configuration numbers (5-8) that are supposed to do this. Do the long press to save one of the configurations, reboots in 5 sec., led bar still on.
Make sure you have the latest firmware flashed.
https://www.airgradient.com/documentation/one-v9/#firmware
The 5th or 6th time I tried this it finally worked, without a firmware update. Odd.