I've had the exact same issue and it is indeed a TurboTax software bug. I have found a solution.
Click "Forms" on the upper right of the screen. Then select "Form 1099-K Wks (ebay)". Scroll down to the bottom that says "1099-K Reconcilliation". In 2b, "Payments for personal property sold at a loss", the box is checked, BUT THE VALUE IS NOT ENTERED!!! Enter the same value as "1" and then "3" should become 0.
It will then not ask you to link schedule C.
TurboTax, please fix this issue!!
