FLAG error in Editor

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The map I'm making has been going great, until I try to make a new flag for the second base. Whenever I try to do it is says:

scripts/items.cs (114): Register object failed for object .

so I went into that file and found this function:

function ItemData::create(%block)
{
   if(%block $= "flag")
      %obj = new Item() {
         className = FlagObj;
         dataBlock = %block;
         static = false;
         rotate = false;
      };
   else
      %obj = new Item() {
         dataBlock = %block;
         static = true;
         //rotate = true;
         // don't make "placed items" rotate
         rotate = false;
      };
   return(%obj);
}

I haven't changed anything with it at all, it just started happening after I closed the mission for the night yesterday. I'm not sure why it won't work, and its just with the flag as far as I know...

Any advice?