I was 90% complete with my taxes and getting frustrated, so I hit, "Do my taxes." I changed my mind and went back, but now ALL that progress is gone. Where did it go?

It has kicked me back to "getting started" and shows nothing even remotely complete.  It took me three separate days working on this to get to this point.  I only needed help with one or two questions.  I'm not about to redo all of that finding and uploading of documents.  How do I get my saved progress back?