didnt get for the fallen(i have 30 cog tags)

[I NL Startux I]

i've got with gears 1 uhm 30 cog tags it says i have 30 cog tags but i dont have the achievement and i was online while i got it...
and i cant get it anymore its not a big problem but still i want the achievement.
i hope yo can help me further.

[Ali Legend]

I had a similar problem with 'you down with E.P.I.C'.. I won a 3 round warzone on each DLC map but no achievement. I emailed Microsoft Customer Support but they did nothing at all to help me