Xperia 1 brightness issue

[Susiebelle]

I have the brightness level at the highest. And adaptive brightness isn't on but my phone is screen is far from being as bright as it was when I first set it up. Any help...grateful

[Uliwooly]

@Susiebelle 

go to 

settings > display > advanced > color gamut and contrast

have you changed anything?

[Xp3r1a]

The brightness level can only go higher with auto brightness turned on.