Xbox One -> ISIC not unlocking after completing The Algorithm

My younger brother just beat The Algorithm after I recommend he try the game, but he didn’t unlock ISIC after completing it. When I went into the character menu to look when trying to help him the only option shown to unlock ISIC was the level requirement and the alternative for beating the story mission wasn’t there at all and there was a blank space where it would usually be. It’s worked fine for me and I haven’t heard of anyone else having this problem so it might be rare, but I’m not sure.

Ive had this problem too. I play split screen and my friend hasn’t unlocked ISIC either, even though I did it solo and got him.