My account got banned for something i have not done

My account got banned for third party software usage. But i dont even hae any program interfering lol. I used to use mklol 6 months ago but then i got the warning from riot then stop using since then. And now out of nowhere i got banned forever? Please revise the decision. I have been playing this gane for 3-4 years. I have been nice and not toxic at all. I'm sure for the 4 years of me playing i have not been reported over 10 times. Please check it back. It must be some kind of technical error.