HSK means head shot kills. If what you’re saying is true, it would seem someone has used your account to hack with an Aimbot and get headshots raising your percentage to an alarming rate which resulted in a ban. No I do not represent BF4DB but this is what I am assuming.

Hey guys, I'm not here to appeal for a ban but I just came back to BF4 after almost a full year of not playing.
I remembered this site, (I used to look up suspected cheaters here) and I searched myself for shits and giggles and it says I have a 23% cheat score.

Why is that, and what can I do to lower it? (I don't cheat, at all. Haven't even been online in almost a year TO cheat.)