Amending 2018 return

I processed my 2018 return using Turbo Tax CD.  I purchased 2019 Turbo Tax Online to do 2019 taxes.  When I went into 2018 return, I made changes, but did NOT save.  When I later re-opened 2018 turbo tax to finish return, it shows no entries whatsoever - appears as a new return awaiting input.  I read somewhere that if you use online version of turbo tax, it automatically saves data.  But I didn't have online for 2018, so why did I lose my data?