This is odd is seems dyndns has stopped forwarding sitegeisha.dyndns.dk to my server, however I tried using SSH using sitegeisha.dyndns.dk and it work, also tried ftp and it worked, tried accessing using other ports and it also worked.
I also checked to see if port 80 was accessible from the outside and it was okay. http://www.canyouseeme.org/
WTF is going on???!!!