Solved
I tried to download my 2018 tax returns, It said I had to "register" so I followed these instructions: https://tinyurl.com/um6bdws. Now it says my 2019 taxes are filed, so I'd like to know how to 'refile' or change my 2019 taxes. I've tried downloading the "turbotax cd/download" to amend it, only to find the download link to the free version doesn't work.
It says my status was 'ready to mail', and following this answer I was able to fix the problem
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