Adobe Express ruined my PDFs?

I think Adobe Express ruined my PDFs. 

1. It rendered blank rectangles for characters with accents. I ended up manually copy and pasting text to fix this.
2. When I download the PDF there is a grey line to the left of some PNGs which were not there previously.
3. There doesn't seem to be a way to undo the PDF from using Adobe Express. I feel trapped and upset because I put in a lot of work into this PDF that I need to fix again.