the ASUS software seems to have problems with identifying devices within Windows. the problem here could just be that it randomly loses track of them so the lights stop functioning.
there's many threads all over the web about people having similar issues with Aura Sync and the Lighting Service especially. it seems to happen a lot more often for people that have uninstalled/reinstalled any of the software(Aura Sync, Armory Crate, Aura Creator, Live Dash) one or more times.
i had the same issues multiple times and have finally had it resolved for the passed couple months. usually the only "permanent" fix seems to be reinstalling Windows and doing a fresh install of whichever version of ASUS control software.
ASUS ROG Strix Z590-E Gaming | i7-11700K \ ASUS ROG Ryujin 360 | G.Skill TridentZ 3466 CL14 32GB | ASUS TUF RTX 3080 Ti | M2: 960GB \ SSDs: 5TB \ HDs: 16TB | Super Flower Leadex III 850w | Fractal Design Vector RS Blackout \ 5x be quiet! Silent Wings 3 140mm High-Speed PWM | Logitech G600 | Corsair K70 LUX RGB | Xbox One S Gamepad | Klipsch ProMedia 2.1 | Anker Soundcore Life Q20 | 34" Alienware AW3420DW \ 55" LG CX OLED | Windows 10 Pro x64