No need for mutagen not unlocking

Every achievement in the game have unlocked for me except this grind fest!

And of course, 10 of the 18 hours of playing have been grinding to this now glitched achievement and I'm stuck at 29/30 unlocked.

I even have the in game achievement as COMPLETED but not the achievement itself!

I've done this:
All characters lvl 10
Replayed a level with every lvl 10 character
Completed an entire level after all characters got to lvl 10
Restarted the game multiple times
Hard reset my series X console
Logged out, then in my profile
Deleted my local save file, and loading the cloud save
Uninstalled and re-installed the game

On Xbox the achievement appears as locked, in the Turtle Lair in the game it's shown as Completed.

Help me!

Xbox Live issue it seems. Many people reporting issues with achievements not unlocking

There are some issues on the XBL side of things. To keep things centralized I will lock this thread.

Please see Xbox currently experiencing achievement outage