Perma banned for using 3rd party software

I've been playing league during the IP boost event. Some losses, victories, big losing streak, one game where I absolutely crushed the enemy team with 30/4/7 and few days after the event, after another big losing streak. I got carried as on mid, got a S+ with my new favorite champion and then my support helped me get fed as .

After the victory screen, I clicked on play again button. The new League client showed some message that I couldn't read because it disappeared too fast and the game quits. So I launch the game again. I enter my password and the game says that I got permabanned for using 3rd party software even though I don't use any 3rd party software.

I even got an email from Riot:

Hello Summoner,

Your account: XXXXXXXX was banned due to the use of malicious 3rd party programs or modifications to your League of Legends client. We believe that all players should play on equal footing in an effort to promote competitive sportsmanship. You should be aware that modifying your League of Legends client is against the Terms of Use: http://eune.leagueoflegends.com/en/legal/termsofuse. We hope you can see that it is unsatisfying to play against other players who are using a tool to gain an advantage over others.

If you wish to dispute the actions taken against your account, you may contact us via this link: http://support.riotgames.com

The only time I can think of somebody wanting to report me for cheating was when I was playing Kled against Ekko in top lane. Every time he was about to kill me I was nervously waiting for Skaarl to return. Skaarl always returned and I won the fight. This tactic worked for me every time we fought 1v1. The enemy Ekko got really mad at me and was accusing me of cheating. I tried to explain to him why I do so much damage, that it was because of the passive ability combined with the Thunderlords mastery. He was saying something like "Kled is nothing without the horse" and so on. Then I assumed that he simply doesn't know how the champion works and I tried to ignore him. Nevertheless, we still lost the game and he probably reported me for cheating.

I do not know if any other software that I have installed on my computer was interfering with the game but I certainly wasn't using any 3rd party software to gain an advantage. The only thing I could think of that could count as tampering with the game was when I put 2 screenshots in the highlights folder of the "one game where I absolutely crushed the enemy team with Garen 30/4/7" because I wanted to make a montage video of some of my good plays later and I knew if I put the screenshots anywhere else I would forget about them.

I really wouldn't want to lose my account. I have this account since like season 3 I think. I even put some money into this account. I even got lucky with the box openings.

I've already sent a ticket and I'll see how things out.

Any feedback would be appreciated, thanks in advance.