Saved AI as a pdf and layers disappeared

[fearless_rhapsody2800]

I was working in illustrator saving as a PDF file - had like 10 layers going on. accidentally closed illustrator and when i reopen the PDF it's flattened all the layers and i cant seem to even edit the individual elements?? it shows up as a 'linked' file PDF.. PLS HELP 

mac user 

[Monika Gause]

When saving as a PDF, you need to have "Preserve Illustrator editability" turned on in the file options. But even then file corruption might happen.

Can you embed that thing that looks like a linked file? We need to have screenshots of how this looks inside the layer in the layers panel. And the Outline view.

What was supposed to be in the file?

Weren't there any warnings when you closed Illustrator?