Issue in my Site - 3

Im my site http://www.preparado.pt in the k2 comments, it appears the Real Name as the Author and not the Nick.

k2 comment.PNG

Here is the K2 users:

k2 users2.PNG

Here is the Joomla Users:

joomla users.PNG

As you can see, in all over my site, the user Marcos Coelho, always appears as "Hitman", even in the Kunena forum! But if he comments in the k2 itens, it appears as Marcos Coelho.

How can i change that to the nick?

Thanks

First of all, please create normal title not 'Issue on my Site -X'. Secondly K2 as a 3rd party extension is beyond our support, you should contact with K2 support forum. Did you check the comments settings inside K2 ?