I have lost a global script!

A very big script has disappeared from my global ->ScriptLibrary, it doesn’t appear anymore in the designer !!!

Is there some way I can retrieve this on my disk. I’ve found nothing (only old versions of the last week)

I have saved global & project but when I do a rollback it doesn’t retrieve the global parts ???

My scripts were about 500-600 lines 

Do you have a solution ? I am on 7.7 ignition version