Barry Whitehouse Signature w/ FFB prefix?

I have two Fijian $5 banknotes with Barry Whitehouse's signature. One of them has the standard FAA prefix, and the other one has an FFB prefix, despite it showing up on Numista as linked to Faizul Ali Ariff. Is this an error or a transition note? I don't understand why anyone would even bother counterfeiting such a low value banknote. Can anyone explain? I'm including a photo to show what I'm talking about.

Hello!
I don't believe it's a forgery. It's just that the FFB prefix has versions with different signatures. Thank you for providing an example! I will adjust the variant to include both prefixes. =)

Also please add you pictures as an example/proof of existence. Always a good idea if catalogs might state otherwise or are not up to date.