Gamerscore random reset

My gamerscore isn't actually gone, I still have the Gamerscore itself. But when I look at my achievement list all the games have been erased and the latest game I played, Mass Effect 2 has been reset to 0/1355 achievements. Which SUCKS because I was literally
3 achievements away from maxing out the game... What on earth is going on?!

Happened to me. I was playing Mass Effect 3 and got a message from someone asking if I knew why his GS had been reset. I checked mine and it's gone except for 1 random ME3 achievement I gained today - and a few other people on my friends list have gamerscore
reset too. I haven't cheated - I don't even know how to cheat!

I was literally going to make the same topic. The same exact thing happened to me, with my gamerscore being reset to zero. One thing I do notice between you and I is that we have been both playing Mass Effect, and then it resets...I'm currently on the phone
with MS customer support now, patiently waiting for someone to talk to.

Glad to know that we weren't the only ones experiencing this. I've never cheated to attain a gamerscore in my life, and I don't know why it would reset

Seen this a few times over the past several months.

It's just a glitch,no idea why it happens but in every case the Gamerscore has corrected itself within a few days so no reason to think your's wont do the same.

You can always check the steps
here & fill out the survey at the bottom of that page if you want.

Also happened to me while playing Reach.