Over the years, I've spent countless hours grinding for XP. I have never used a single exploit, and have always played fair, knowing I could get reset if I used any unnatural methods. That being said, I've lost my skills and unlockables SO many times, and I cannot seem to figure out why. Someone else might have asked this question, I'm unsure. However, I've refused to work towards any unlockables or skills, as they have been reset in every update that comes out.
I don't expect to get my skills just handed back to me, I don't think things even work like that, but I would like to know why this happens to me repeatedly. The only known time my skills SHOULD have been reset and were was when I was forced to change my gamertag.