Did Not Recieve Terminus achievement

[Cornanator07]

So last week i was finishing the campaign on heroic for halo4 and I'd found the last of 7 terminals yet i didn't recieve the achievement, I contacted microsoft and they said they couldn't do anything, so I'm now like wow thanks alot 343 for screwing me like a steam train. Anyone else had this or similar issues talk to me

[xkill88]

there are 8 terminals i think,

[Cornanator07]

no one is masterchiefs file which i already found