You can simply contact the staff with these 3 Methods:
1. Support Page
You can visit the above linked support page. It has a contact E-Mail address listed.
2. Contact Admin Button
Click on your profile at the top right corner to open a menu. This menu shows a Profile, Settings, Contact Admin and Logout Button. Simply click the Contact Admin button and your default E-Mail software with the contact E-Mail address already filled in will be opened.
3. Private Message
Go to a Moderator/Admin Profile, click on the Controls button and a menu should show up. This menu has a Send (user) a private message button. Click this button to then send a private message.