Nostalrius Begins - Quality wow vanilla realm (1.12)

character sanfori
server pve

my brother was playing, on sanfori killing mobs, then he made a macro to heroic strike and overpower to bind them togher, short after he got dc ,and it say i am banned, i know that it is my responsibility to make sure he does do anything stupid on the acc, but just want to know if this is a wrong ban or he did somthing wrong,

You shared your account with another person so it will stay banned.