Also any new creep created will work but not the old creeps

I am running the following code but only one name is appearing in the console and It also happens to be the only creep that is doing something. I don't know why It all worked fine last night, but now it's all broken for some reason. Could the server maintenance have done it?

for(var name in Game.creeps) {
var creep = Game.creeps[name];
console.log('Name : '+name);

}