Item with the same ID already exists.

[Goad]

I created a new configurable item that has 3 simple items attached to it (ex item is a hat, and there is 3 options for color of hat)

This is the last item I created and I created it 2 weeks ago and it worked fine up until today. I havent made any major changes or anything to my site. The following is the error I am getting on both the front end and when I try to view the configurable product in the back end admin section.

Item (Magento\Catalog\Model\Product\Interceptor) with the same ID "500" already exists.

What can I do to resolve this quickly as I just launched a fairly large ad campaign. I have full access to everything, just need to know what to do.

[Goad]

I found an article that suggests to run the following query, and it returns nothing....

SELECT * FROM cataloginventory_stock_item
WHERE product_id in (
    SELECT product_id 
    FROM cataloginventory_stock_item
    GROUP BY product_id
    HAVING ( COUNT(product_id) > 1 )
)

[muddennord]

Did you find any solution on this?