High Sierra update deleted my notes in Preview

I use the Preview application for making notes on content given to me at school. With the new update, all of my notes have been deleted and I was wondering if there is a way to recover the notes without Time Machine.

(Under Markup Toolbar -- then Note (like a sticky note) -- allows you to write in the note and place the note within the pdf file -- note is still there, but contents of notes are deleted)