I was a level 100 in Gears of war 3. I turned my Xbox off for one day and all of a sudden I found myself at level 50. I turned it off, played everyday for a few months; I dropped to level 12. It took me few months to reach level 59. Today, I was playing (as a level 59) until the match was over. I went to the home screen and I was dropped to level 12.
Why is this happening?