SAI USERS I need your halp

I really need help ;A;

After I saved my image on Sai I exited out,turned my computer off, and went to get a snack.

One hour later I turned on my computer, went on sai, opened my picture, but ALL OF THE LAYERS HAD MERGED (and I did not merge them myself). Now i cant color my picture because the color goes over my lineart.

I tried putting a layer over the layers that had mysteriously merged but it doesnt allow me to draw anything on it.


I need to color this drawing ;A:
What do i doooooooo?