Bringer of order achievement not unlocking

I’ve played Diablo 3 alot across both Xbox One and PC. I’ve purchased the Ultimate Evil Edition on both and I am trying to get all the achievements on Xbox One. One of the achievements is glitched on Xbox called “Bringer of Order”, the description is “Complete Act V with a Necromancer”. I finished the whole campaign with a Necro (from Act 1-5). It didn’t unlock. I started a fresh necro character and did the same again, it did not unlock either.

I have uninstalled the game and done it again - nothing.
I have cleared saved data (local saved data) and did it again - nothing
I have tried doing the entire campaign offline - nothing

What can I do to fix this?

I also have this problem.
Ive completed Act 5 on a number of occasions… Be it Story, adventure and hardcore, I’ve tried everything and the achievement will not pop. The in game challenge had unlocked the first time I completed it.

Please… Is there anyone with any real information about this that can actually help?