Keep submitting GM reports with a reasonable wait time in between. Harassment may not be the right category, but I'd say it definitely falls in the definition of Inappropriate Behavior (http://support.na.square-enix.com/fa...la=1&kid=68216) if the FC leader refuses to do even as little as remove you from the FC.

I can't believe a GM won't intervene, but at the same time don't abuse the support system trying to make them, or you may be penalized for that in addition to having your situation resolved.