The weird save issue happens to me all the time, but it actually helps me out. It's really annoying that i have to redo assessments to get new perks and attachments, but for some reason, I get the bonus XP when I get them, and it goes to my level up, but the fact I got the perk does not save, so I get the perk a match or two later, when it resets, and get the bonus XP all over again.
A lot of people wouldn't admit this, but I prefer having my stats save and accrue over my XP being accurate. It's more fun to go back and see how many headshots than it is to say "oh i have 186000 XP!!!1!

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