hello,
I have got the same problem, I used to be in beta channel, out of nowhere I'm in canary channel right now, and after the latest windows 11 pro update I am unable to adjust brightness. Could you help me with it?
The brightness issue is a bug in the latest builds.
If you are in the Canary Channel the only way
out is to do a clean install.
Backup all important files, etc. and then use the
MCT to clean install. https://www.microsoft.com/en-gb/software-download/windows11