Larian Studios Forums Baldur's Gate III Baldur's Gate III - Technical & Gameplay Problems See Invisibility from fake eye seems very unreliable

I have a main character with the artificial eye that's supposed to give you permanent See Invisibility, and the icon for the ability is showing next to the character's portrait.
However, I also just had a Duergar become invisible while in melee with my main character, and they just vanished, walked away with no attack of opportunity, and I was unable to attack them on the next turn as I couldn't see them. This isn't the first time something like this has happened, either. There's no save or ability check happening, the see invisibility effect just sometimes doesn't work.
It seems like about a 50/50 chance whether an invisible enemy will be detected any given time.

Did the Duergar pass his saving throw? It should show the little save success icon if so.

For See Invisibility, anything that is invisible has to roll a DEX save.