Allow me to explain the situation
Properly
Your ban was a result of admins quickly doing a investigation onto your profile and noticing that you have an abnormal amount of warnings and mutes for racism as seen here:
at certain points it is a admins responsibility to ban players that are simply abusing the warn system, and for this they felt that you where just going to be racist, over and over again, the term 'N*g N*g' which you where saying 'wasn't racist' in this specific occasion was infact racial remarks, A quick google search found;
Variation on "n***er", evoking stereotypical African tribal chanting, dancing etc. Although very offensive today, many people wouldn't have regarded it as such in the past when it could also just mean "idiot". Although it is also northern English slang it is still very offensive outside the norm and be considered 'loophole racism.'
you where banned for over
ELEVEN accounts of racism and as you can tell in your warns? the admins ( and players ) where fed up of your shit.
Simply put; If it's a permanent ban, wait a few MONTHS, yes, I said months.. to realise that your repeated racism is not acceptable in any social situation. Come back, and apologise.