LuckyBlock has a previous unresolved case against them, according to my list. I can try to call their rep here, but I guess that'll be useless, as my previous invitation to attend the said case failed to reach them. I don't think they even use their rep account anymore, it's been collecting dust for years.

That said, I guess your best chance will be to try to escalate this to CG or AG, as they seems to respond there.