You need to send in a ticket, after they send you the first automated message (if they do) tell them you need to talk to someone that can help you with this situation. When you tell them you were not using anything that gave you an advantage over everyone in the game, they will probably tell you you were and they are not allowed to give you details because it will hurt their investigations or some shit like that on how they find out people were using the 3rd party program. That is bullshit. They need to provide proof that you had an advantage over everyone else or that you were using the program they banned you for. If they still refuse, you need to ask to speak to someone higher up so you can talk about this. That is unacceptable to ban someone that knows they did not use a 3rd party program that was not allowed and not have evidence.
I have been trying to help a lot of people with this same problem the past few days.
Please let me know how you do with this and I would like to know what the support team says to you!