Cant unlock "Classified data", in Waypoint.

I’ve unlocked a couple of Terminals on Halo MCC. I go to my Xbox 360,then halo waypoint & hit classified. I put inthe provided code & its says I haven’t unlocked the terminal. Is it because I did this on the Xbox one, unlocked the terminal. And went back to the Xbox 360 to unlock the classified achievement.

It is because you did this on the Master Chief collection, not Halo CEA