if alphabetically ordered, victorfabius1 is after victorfabius.
i suspect that if you create any other ID the one preceding your ID can possibly be created. All it takes is to take any user ID and remove the last character. That’s what spy bots do and then actual human user collects the harvested user IDs to build scams.
one of such example is to remove last character from gmail and it will give you the site domain gmai.com located in Beliz specifically for collecting information from gmail members.
the best remedy for that is exactly what i do: I don’t purchase neither sell from internet.
my SOLID IT background just would not allow me to do that.