Did you notice the partial collar before you sent it in? Is it miss labeled, or can you see it in the slab?
I thought it had a minor misaligned die; it never occurred to me that they would grade it as an error coin without my request. The error is extremely minor and of no consequence to the value of the coin, other than to cut it by thousands of dollars by not allowing it in the registry.
You should definitely contact them. I think it was a computer issue. You, should be able to see a partial collar even, in the slab.