I have been playing the first time over xbox live 6 months and 1 week ago and I can't unlock the dedication achievement I even tried to change the time zone and it won't unlock, does anybody can help me here? I have played over 10 game this week and win about 3 of them...

PS. It's the last time I buy a game from EA after the dead space online pass multiplayer (nobody on the game) now Crysis buggy achievement...