DELL G15 5521 SE - Toggle keyboard backlight (f5) not working when device boot

The Toggle keyboard backlight button is not working at all during every single time when the device boot. There is no problem with the key because the key will be functioning well right after I opened awcc manually. All of my drivers are the latest version. When I chat with the CS team, they were just beating around the bush with me. Telling me it's my keyboard spoil or not? , installing latest driver, etc.