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When make GetItem call, ItemType.getSeller().getEIASToken() always returns null. What is wrong?
A seller's EIASToken, <Seller>..<EIASToken>.. </EIASToken>..</Seller> is not reported in GetItemResponse payload, even though the API caller is the owner of the item. As a result, attempting to retrieve the property directly via ItemType.getSeller().getEIASToken() operation returns an empty object : null.
You can get a seller's EIASToken directly through either GetItemTransactions or GetSellerTransactions API call. Although either APIs always return a seller's EIASToken property in any DetailLevel, only GetItemTransactions reports the property to any caller.
You can also get a seller's EIASToken indirectly if you need to retrieve the seller's EIASToken after making GetItem API call. What you could do are:
1. extract the seller id: Seller.UserID returned in GetItem
2. Make GetUser API call by specifing the seller id obtained in the request