Brightness on Lenovo not working in Pop!_OS

Brightness on Lenovo not working in Pop!_OS

On my old laptop, a Lenove IdeaPad identified as Intel Core i7-3632QM processor, Intel Ivybridge Mobile graphics by Pop!_OS, the brightness is not set. Although the Fn key (F11 and F12) are working shown by on screen display with brightness icon, but the is not taking...