Stop an already approved wordpress commenter

How do I stop someone from commenting if I already approved them…

I have his IP, e-mail and username he posts with!!

I have this,

“Car hire”
“[email protected]”
“123.238.34.42”
“123.238.34.37”

But he can still comment. Should I remove the quotes!

Also I have this in both spots. Comment moderation and comment blacklist.