Unable to turn off keyboard backlight on 15-5559

Hi All,

I recently got an Inspiron 15-5559 Signature edition from the Microsoft Store. I've been trying to turn off the backlight on the keyboard but none of the methods allowed me to do so.

I've tried pressing Fn+F10, as well as just F10 while the Fn key is locked.

I have also installed Quickset but that isn't working either. The slider in Windows Mobility Center moves but it doesn't change the backlight brightness at all. 

Lastly, changing the keyboard illumination settings in BIOS doesn't change the backlit levels either.

Any ideas on how to get it to disable? Thanks