Well I managed the XML in the 15th so I'll try to help you.
This has to be a problem with the XML link, make sure there are no spaces before or after:
http://www.dtclan.co.uk/squads/1184051863/squad.xmlThere is a disconnect between your ArmA 3 profile and the XML, as it would display some information if you were using an incorrect alias. I checked the XML and everything is properly setup from what I see. Your ID is correct on the XML, and I made sure you listed a valid one.
If all else fails, delete your current ArmA 3 profile and make a new one. Like I said before, make sure your username ("PFC Alexander") and the XML link have no spaces before or after them.