Brightness hotkeys(Fn+F5 for decrease and Fn+F6 for Increase) are not working on Ubuntu 20.04 Lenovo Ideapad-5-15ITL05

[akash rayhan]

But I can change brightness from brightness slider.
I used the command "watch -n1 cat /proc/interrupts". But when i pressed the brightness hot keys id didn't increased the interruptions. I also used the "acpi_listen" at that time it didn't feedback any output when i pressed the brightness hotkeys. Again I used "sudo showkey -s" it also didn't feedback any output. I updated the bios recently but the issue still persists

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: linux-image-5.8.0-59-generic 5.8.0-59.66~20.04.1
ProcVersionSignature: Ubuntu 5.8.0-59.66~20.04.1-generic 5.8.18
Uname: Linux 5.8.0-59-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.18
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Fri Jun 25 18:11:50 2021
InstallationDate: Installed on 2021-06-24 (0 days ago)
InstallationMedia: Ubuntu 20.04.2.0 LTS "Focal Fossa" - Release amd64 (20210209.1)
SourcePackage: linux-signed-hwe-5.8
UpgradeStatus: No upgrade log present (probably fresh install)