Asterisk persistent on Level

I have this issue:
Just after opened a level appears an asterisk near level name.
Also after saving it doen’t disappear.
When loading another level it ever ask me to save also if no changes made.
What’s wrong?
I fear it’s started since I’ve made a “Fix Up redirectors in folder” function that created many problems.
Any other had this issue?
Thanks in advance.

Hi guys, I’ve just found the solution. I report it hoping it can help.
It’s really crazy stuff!!
Reason locking save asterisk was a particle that emits lights, and these lights are set to High quality!!
Can you believe it?
Here the screenshot.

Ps. All happens inside a construction script. If moved after a BeginPlay of the eventGraph obviously I don’t have this issue.