Adobe update has compressed my layers

[geraldinel92662865]

Hi, I went to open a file I was working on a few days ago, and i think adobe illustrator has updated itself which means all the layers i was working on are now compressed into one layer. Is there anyway to get back the original format with layers? This is going to set me back ALOT 🤦🏻‍:female_sign:

[Doug A Roberts]

Was the file saved as AI or PDF? What does the file look like in the layers panel?

[Ton Frederiks]

Which version are you using now?

Was the file created in a newer version?

Did you save a pdf without Illustrator editing  capabilities checked?