Like always it is Ebay to blame for your negative. They simply want all us sellers not protected by them to receive negatives and low ratings even when not deserved. They wont remove the negative even when it is not your fault. Unfortunately, sellers are now at the mercy of a few bad apples and the extremely poor setup of Ebay's rating system.

Unless you know someone and can get any and all negatives 'revised' or removed which certain sellers can, then you are stuck I am afraid

Another amusing twist with the Ebay rating system is when a buyer makes a mistake and wants to return the item. Even that counts as a negative on your account and ranking. Figure that one out.