Error Code 21916582 “Variation Specifics provided do not match with the variation specifics of the variations on the item.”
You can receive this eBay error when two variations in the same parent-child group have the same variation options. For example: Sku XXX1’s variation option is “Red, Small” and Sku XXX2’s variation option is “Red, Small” as well.
They can be easily identified after the related variations are exported. You can then update and save either through the user interface or via bulk update.
Via SA UI
1- Find the parent and click edit.
2- Go to the “Variations” tab and see if the variants have the same variation options. If this is the case, click “Edit Option Set”.
3- Click one of the variation themes and start editing the wrong option types values or adding new values to the variation.
4- Select all the parent-child products and delete and recreate the variation listings. We can’t use product data update because eBay doesn’t allow you to change the variation listings with the product data update.
You can use the article below to get detailed information on how to relist a product on eBay.
You can use the article below to get detailed information about changing variation options with a bulk file.