No Option to Download 2017 .tax File, Can Only Download PDF

I am using TurboTax Desktop and need to amend my 2017 tax return, which was done in TurboTax online.  I have followed numerous TT help articles, to no avail. This article from TurboTax says simply go to TurboTax and select "Show Documents From 2017", when I do that, my only option is to download the PDF.

 

How do I obtain the 2017 .tax file?