Oh that sounds terrible. In this instance I would send an email directly to the fresco help team.
You can get to it through the bug report option under Help in Settings.
Or if you don't want to open Fresco, incase this prevents anything you can use the email address of frescohelp@adobe.com
Give them as much detail as you can, such as device, and if anything happened such as errors, power or internet outage so they have information to go on to help them to help you,
Hope they're able to save your work!