I've been Perma-Banned for Third Party Software even tho I haven't used any...

I've contacted Riot Support and but all they told me is that they would move my message to someone who would take of it. But haven't heard anything yet... and I'm still perma banned. I haven't used any Third Party Softwares and only given my account once to my brother (and with my computer, so no way for my brother to get any cheats anywhere..). So I assume that I just been toxicly reported by someone else. But I would still like to get my account back for the new season... Any Riot Assistants who can help me out... pls :(