Hi, welcome to the site.
Just click on your avatar. It will take you to your trophy room and stats page, then click the link to your profile page. It might take you directly to your profile page.
At the top of the page right hand side, look for private messages. click on it.
Just enter admin
then the subject and message and hit send.
Hope that helps.
good luck and pleasant solving.
Courage is the art of being the only one who knows you're scared to death.