Hi Jasmine,
The best way to avoid that ever happening again, is to use the "Save As"
option as opposed to just "Save". Thus, saving multiple times (e.g. Edit-1, Edit-2, Edit-3, etc.), along the way as you're building your project.
Then if you have a crash, you can always go back and open your previous saved pds (e.g. Edit-14), and avoid risking loosing all your work.
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