Layers Gone.. or Cleared? Need help.

I was drawing on my iPad with Fresco, and out of blue, the app froze and the layer went black (not my whole screen, only the work area went black). I reopened the app, and found out that almost half of my layers were cleared. Layers were still there, but nothing was in the layer. 

I worked on this drawing for many hours, and now it's gone. I know I should have saved a backup file, but it's too late to regret.

Is there any way to recover this?