Just to reiterate what I said in the last post; I highly suggest not responding to any of their messages, it gives them the attention they're craving.
Simply block and report them, don't send them any messages or reply to anything they send. Just delete whatever they leave on your pages and ignore them via blocking.
Simply block and report them, don't send them any messages or reply to anything they send. Just delete whatever they leave on your pages and ignore them via blocking.