We have update the Unreal Tournament 2004 protocol this week, meaning that you may need to change the query port on your server monitor to make it work.  If your query port was 7787, you should now change it to 7778. 

If your game port is anything other than 7777, just add 1 to your game port number to obtain the likely query port number.  For example, if you UT 2004 game port number is 6565, add 1 and get 6566 - this would now be your query port. 

If this doesn't work for you, feel free to contact us on Live Support or email support (both available via the Help Desk link) to get some help.