Does anyone know how to cancel WoW?

Mainly due to the fact that they ignore/ don't look at player reports for harassment. I get the run around telling me to right click on player and report for language which does absolutely nothing because it have already been done that way almost a dozen times.
I do not want my 15 yr old child subjected to that kind of vulgar language and cyberbullying no longer.
Obviously this kind is of behaviour ok with Blizzard because since this keeps happening.