What wrong with .co.cc domain?

I have managed several blogs. Some of them under the name of blogspot. Some are paid domain. The rest is under the free domain co.cc
Recently I find annoyance with co.cc domain. One of my blog is not accessible. When I access, it comes to co.cc page and state that my domain is under examination.
I do not understand with that trouble. what kind of examination is it? The worst is co.cc did not give any confirmation or warning or anything about this examination.
It said that the examination lasts in 24 hours. Unfortunately my domain has been under co.cc examination for more than 24 hours and still no accessible. I really do not understand with co.cc. It is free but also free of solving. It sties a problem