Out of all Windows 10 issues, several users encounter one common problem: Windows 10 brightness control not working on their systems. Due to the weird bug, users cannot increase or reduce their brightness levels on Windows 10 systems.
Source: https://blanchektechnologyhub.wordpress.com/2021/03/10/windows-10-brightness-slider-not-working-here-are-the-fixes/
screen brightness
Windows 10
norton.com/setup
www.norton.com/setup