Finding the SKU of a parent listing

I have a parent listing with one child variation. Under Manage Inventory, I see the parent listing with a SKU under the SKU column. However, when I attempt to use the Variation Wizard to upload a new variation via spreadsheet, I get an error. It is saying “We’re unable to find the Parent SKU: [a-sku-string]”

The SKU shown in my SKU column under Manage Inventory is completely different to the skew mentioned in the error message.

Why is this? Are there two different SKU’s for a product and if so, how can I verify what product the SKU in the error message refers to?