Overload Specialist achievement not unlocking on Xbox One

I was finishing up the last ME2 achievements on my road to 100% the Legendary Edition when after using Overload on way more more enemies than should been necessary I noticed it hadn’t unlocked. I checked my progress in the Captains Quarters, and though it said I had 25/25 the achievement was still grayed out. It didn’t unlock in game or in my Xbox profile itself, despite me fulfilling the conditions.

I’ve reloaded pervious saves and got 25 Overloads again, started a new character and done the same and deleted and reinstalled the game to no effect. 

It sounds silly, but I’m a completionist and being unable to get this last achievement has honestly killed my desire to move onto Mass Effect 3 if I can’t somehow unlock it.