Flux sometimes works, but mostly not

[flux_user_55]

I don't know how much information is required, but I downloaded Flux about a week ago. It's worked randomly once. Most of the time, including now, it doesn't work (didn't reduce the blue light, even though it was active and running). Trying to change any of the colours didn't do anything. And this is all at "sunset times" – it doesn't do anything.

I have a Microsoft Surface Pro 7 which is running Windows 10.
Flux verison is 4.120.

The Windows "night light" is turned off – not that that ever worked properly either.