hacker dilema

malicious hacker

I have a malicious hacker that is constantly hacking one of my hosting clients wordpress site i have tried everything to stop this hacker but nothing works.

I have a good firewall and i have event tried every wordpress security plugin there is, nothing works.

someone let me know what type of server security fix i can do to stop this malicious hacker that is just attacking this one wordpress site

thank you for the help

Alex