All my World Outlinear disappear after reboot

Hi guys! Thank’s for watching this question
So, yesterday I was creating some basic stuff like texture distance and close-up, basic AI intelligence, some blueprints animations for enemies etc…
Today morning, when I opened my project, I discovered that all my world outlinear was disappeared…
The “world” now is called “Untitled”
I really don’t know what’s going on, it’s the first time this happened!

Waiting for your replies, thank you!