Adjusting brightness is not workng and pressing brightness buttons cause system shutdown (while booting on discrete video card)

Recently I've bought Lenovo loq 16aph8, installed Ubuntu 22.04 LTS and faced several issues. One of them is the system crush (power off) when pressing brightness adjusting buttons (F5, F6). Otherwise sometimes it makes the screen black (zero brightness), sometimes it triggers microphone mute button (F4). I've tried to change and update grub settings like in these posts, but it didn't work:

https://www.reddit.com/r/Ubuntu/comments/v97arf/problem_with_brightness_control_using_ubuntu_2204/

https://bbs.archlinux.org/viewtopic.php?id=286357

Ask me about details, I am not sure what information is needed to solve this issue.

Some video driver details:

lshw -c video:  *-display                        description: VGA compatible controller       product: NVIDIA Corporation       vendor: NVIDIA Corporation       physical id: 0       bus info: pci@0000:01:00.0       version: a1       width: 64 bits       clock: 33MHz       capabilities: pm msi pciexpress vga_controller bus_master cap_list rom       configuration: driver=nvidia latency=0       resources: iomemory:7a0-79f iomemory:7c0-7bf irq:75 memory:a0000000-a0ffffff memory:7a00000000-7bffffffff memory:7c00000000-7c01ffffff ioport:3000(size=128) memory:a1000000-a107ffff  *-display       description: VGA compatible controller       product: Advanced Micro Devices, Inc. [AMD/ATI]       vendor: Advanced Micro Devices, Inc. [AMD/ATI]       physical id: 0       bus info: pci@0000:05:00.0       version: c2       width: 64 bits       clock: 33MHz       capabilities: pm pciexpress msi msix vga_controller bus_master cap_list       configuration: driver=amdgpu latency=0       resources: iomemory:7c0-7bf irq:43 memory:7c10000000-7c1fffffff memory:a1200000-a13fffff ioport:1000(size=256) memory:a1700000-a177ffff  *-graphics       product: EFI VGA       physical id: 2       logical name: /dev/fb0       capabilities: fb       configuration: depth=32 resolution=1920,1080

UPD: It seems that the problem is related to the graphic card drivers (nvidia). After booting in the dynamic mode with amd-graphics the problem disappears. Moreover, after booting again with discrete card the problem seemed solved and brightness button worked, however after several pressess - the system shutdown again and brightness was again set to the max level with the same problems with buttons. Additionaly, I've found exactly the same issue here:https://forums.developer.nvidia.com/t/brightness-not-working-after-upgrading-to-ubuntu-22-04/224227

There's also a fix for older AMD Ryzen 7 6800h, but I have AMD Ryzen 7 7840HSI can't change brightness on ubuntu 22.04.3 LTS