Ip Banned For No Reason

Got Ipa Banned For Multiple Login, My Friend from same flat with same internet becouse we both playing runescape and using sythe, he used my discord name on hes sythe idk what exactly hes been selling, but i got banned for no reason, i dont even know what he did , i didint do anything wrong , im using this sythe account since 2011, never had any warning , or anything like that, so please help me with unban its never gonna happen this again !! and keep hes account banned but not my one, i didint do anything wrong !!!! Sythe: S0b1esk1