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This looks more like a cacheing issue though. You can try running a rebuild and restart, that should reset the cache buster.
What do I mean for ''fake account''? Some users create different account for different reasons:
Ais a professional user in your forum and now he has an elementary question!
Acreates another account to ask his simple question.
NodeBB core doesn't have anything to prevent this. But plugins can be made to prevent multiple accounts from the same IP etc although it can be easily by passed.