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I've had a Gold Membership for quite some time, but over the last couple months I haven't had internet to connect to. During that time I've been playing AC: Revelations and got most of the achievements.
So just the other day I got internet again and when I tried to sign in it kept giving me errors and instructed me to redownload my gamer profile. So now all my achievements are gone for AC: Revelations, but my saved game still works.
Is there anything I can do to get those achievements back?