Christian, and Surname hack needed!

[The Slug]

Hi,

New to Vbulletin and how the tech bits work so have left well alone, so I have a standard v4 install with current updates. I have Spam-o-matic installed and that is helping alot on our forum but of late we are getting lots of spam attack's each day trying to join, the common factor is the Christian name and Surname will be the same.

Is there a way to make the system check if the Christian name and Surname are the same and if so just ban the user or have Spam-o-matic do it???

I keep blocking the ip addresses but they just change to new ones and start again. now getting 15-20 new fake accounts each day.

Any help would be great in how to help control these issues.
Thanks.