I'm sharing with you the information below. It appears that the amend function for TurboTax online is currently down. I think the instructions below will help you out.
https://ttlc.intuit.com/replies/5567856
*** I am NOT a tax expert. I am a seasoned TurboTax user, and volunteer to provide assistance to TT users. Nothing I post is to be considered TAX ADVICE; I bear no legal liability for responses.***
