Hello @graham-cz, it would help to know what all configurations you had enabled from this policy. But to take a guess, the Keep Screen On option might be turned on in the policy from Kiosk Lockdown > Peripheral Settings > Display. When you configure this option, Hexnode will keep the device display always turned on. If you attempt to turn the device display off, Hexnode automatically turns the display on, causing this behavior. To remediate this issue, you can either disable this option or disable the power button so that users cannot turn off the device display. You can disable the power button in Kiosk lockdown mode from Kiosk Lockdown > Peripheral Settings > Hardware/Software buttons > Disable power button.
Cheers!
Zach Goodman
Hexnode UEM