hdr brightness upscaling calibration is not saved after clicking 'save calibration'

[Vectus888]

I've just installed the app and my main goal is to fix the HDR that doesn't look good on MacOS if not using the native apple displays (see this reddit thread as a ref - https://www.reddit.com/r/MacOS/comments/18392uq/why_does_hdr_look_like_garbage_on_macos_unless/).
People advised this app can fix it, but I'm having an issue: when trying to save the calibration it just goes back to the default setting. Am I doing something wrong?
Here's my monitor data:

Not sure what else may be needed, so let me know if there's anything else. Please help 🙏

[waydabber]

The upscaling calibration is meant to define the max brightness level for the brightness upscaling feature. You can change the birghtness itself using the app's brightness slider afterwards. The feature is not meant to generally fix HDR issues with the display.