Which policy does my name violate?

My tag used to be ßßßßßßßßßßßŜ, which doesn’t violate any of the naming policy. Nevertheless, blizzard have forcibly changed it and refused twice to elaborate on which actual rule it infringes. If you don’t want me to have that name that’s fine, but you can’t arbitrarily decide on that with rules that you won’t disclose.

It’s 12 chars, has no spaces, has no symbols, and no numbers. It’s not a legible word of any language, so it literally could not be perceived as offensive. If there’s something else that’s not allowed, it isn’t on the naming policy and you need to change it.