She mentions that they're channels she doesn't follow.
I get messages like that too. They get sent to my inbox and not the notifications box, so it's not through the following feature. There are some users who seem to collect lists of usernames (from channel walls maybe?) and more-or-less spam with messages promoting dramas every so often. And I also get duplicate messages sometimes.
@shaldane168 Have you tried asking them to remove your name from their lists? I wonder if it would even be effective though.