I made a clean install of KDE Neon a few days ago and everything has been working well, except for one thing. I can't change the screen brightness, the screen is pretty dark and I'd definitely want it brighter.
I've tried changing the power management settings but nothing happens when I move the brightness slider. I have an AMD Ryzen 5 3500U CPU with integrated Vega graphics. I've been trying various "fixes" on the internet but nothing has worked at all.
Can someone give me some guidance on what to do to fix it?

EDIT: After running xev -event keyboard the F buttons work and i can change brightness with F2 and F3. However, the brightness doesn't actually change.

I have the same issue with KDE neon 5.21 and CPU AMD Ryzen 7 4700U with Radeon Graphics. Any ideas?

I have the same brightness with KDE 5.24 on Kubuntu 21.10 with AMD Ryzen 9 5900HX. I also have a discrete nVidia graphics card and when I manually switch to it, the brightness can be changed, but not on the integrated AMD graphics.
The info windows says the graphics processor in this case is AMD RENOIR.