No one can see your tax return so we would have no idea if you upgraded to a higher edition to complete the amended tax return.
If you followed the procedure to amend a tax return using TurboTax and did not upgrade to a more expensive edition to complete the amended return, then there would be no charge to amend the tax return.
See this TurboTax support FAQ for amending a tax return that was completed and filed using TurboTax - https://ttlc.intuit.com/questions/1894381-how-to-amend-change-or-correct-a-return-you-already-filed
