PHPBB.NET Support

Hi, just tried to go to my forum that i administer and i have a plain page with "Account Suspended" http://tesl.createforum.net. I have had no emails as to why this has happened and there is no other info on the page.
I've contacted the creaters many times but have had no response.
Does anyone know what possible reason there could be. It has only been live for two weeks!

Graham