They probably had a mistake and just did it accidentally but we don't know if there's deep intention about those duplicated application.
This must be the concern for managers because most of them can't even check each of their participants.
i thinks is normal , because manager can make a mistake. but if scammer using name of profil its very carefull and your mine will gone.
It's normal that manager commits mistake, there's no perfect in everything but this is a different issue for having a mistake the way they handle a campaign and to those abusers.
There are managers that are committed to their work but I'm saying that not all of them are like that. As I've said, they can't even check each of their participants so if there are problems like this, someone who has concern and wants to contribute and clean this type of mess, address this to the appropriate manager.