Below is the Turbotax FAQ for Amendments. The steps required can vary depending on how you originally filed the return you are now amending. Please visit the link below and begin by selecting the year you are amending and then the version (online or the desktop) that you originally used to file the return. You will then be provided detailed instructions based on your selection.
You can also try updating the software. For Instructions, please visit: https://ttlc.intuit.com/questions/1901183
https://ttlc.intuit.com/replies/3288565