Unjustly banned for malicious 3rd party programs?

So today I attempted to log into my account and received the, " this account has been temporarily suspended" messaged. I checked my email and riot sent me a message saying I used 3rd party programs to alter my league client, which I didn't. I don't understand what they mean by this? I haven't had any problems playing for the past 6 months and then, BOOM, this shit happens. I don't have the skills to alter anything besides my email address lol. Can someone help? I submitted a ticket but I doubt its going to do me any good. How can they ban me without proving that I was using a 3rd party program? Especially when I WASN'T using one.