You are not the one who committed the evil, but it's someone or group of people who stay around that area who committed the evil, which has affected your own IP and registration.
So what you can do is either pay for the evil or apply for your account to be whitelisted by
by person who have access to whitelist users It's just how the forum has been designed to operate to reduce the number of users who register from a banned IP address.
The right and correct answer is already stated here as this speak more I am about to say. But in addition to this many pass through this issue of IP just as you experience but just be determined by doing the right thing as guidelines is already given.