If you have a copy of the original .tax2019 data file from after you filed and before you amended, then when you open that file, and go to the File tab and use the "Check Filing Status", does it say accepted?
You might use the File tab -> File a Return, and check the file by mail option and then print for filing so that TurboTax will think that you mail filed. It might be blocking the amend because it does not think you have filed the original return yet.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
