Ban accounts with IPs from china, russia, venzuela, indonesia, india, etc = home of the scammers.
Hi there, your post is very offensive. Don't make it general for those countries as bad english speakers, I showed your post on my Indonesian workmate and he want to lay a hand on your sweet face if given an opportunity. Please don't say stuff that will insult others just because you're good. Its better to have a nice attitude than a smart mind but without ethics.
There is a reason people block all communication with nigeria, because the majority of scammers. Sometimes you ban the entire place for the greater good since the majority are scamming cockroaches.