Setup DKIM on IceWarp

Hi,
I've previously check in on a guide setup on your Article site under support.icewarp.com.

https://support.icewarp.com/hc/en-us/articles/115000302847-How-To-Setup-DKIM-For-Your-Domain

This is now locked for some reason. Is there any way to access this article or another similar describing how to setup DKIM for a domain on IceWarp?

Best regards,

Simon