I found a temporary solution for myself that might work for anyone else.
Run command prompt in administrator mode > Type powercfg -requestsoverride PROCESS "Corsair.Service.exe" SYSTEM
The corsair.service appears to be writing a lot of fan related data which I guess somehow prevents the pc from sleeping in my case. Ending the task via task manager just results in it being initialized 1 minute later even with ICUE closed as its by default set to do so in windows services.
If doing the powercfg -requestsoverride doesn't work for the corsair.service.exe then try another corsair service from task manager.
