I did not use any 3rd party programs or modifications

hello i am very confused about why riot decided to ban me from league forever. I promise i did not use any 3rd party programs or modifications in game and I will never use these kind of thing in the future in any game. I spent a long time in league and quite a lot of money, I hope you can give me a chance to play league again with my account. And please provide some evidence if you keep saying i used cheat!! Because this is just slander!!!! Thank you