(Solved) All another files are opened, but only one file isn't opened

The file I want to open took 6 days - I invested all of my time making this for 6 days.
I was able to open this file just 5 hours ago, but now I can't open. - so I don't think this is a file problem
I tried to turn off the desktop, I tried to update(as my version was old version), I tried old version, I tried to upload for private mode - it wasn't opened, I tried to open it for my phone, I opened another file and opened the file I want - All of these solutions are no use.
I'm not good at English as I don't use English in my country, so maybe I passed the solution. I don't believe it is the file's own problem, and it must not be the file's own problem.
Musescore asks if I want to recover my latest session(I can't understand what it means). If I click yes, it is turned off, and if I click no, it is turned off too. It really makes me mad - I think the word 'mad' can't express my feeling.
I really dedicated to make this file, so I need your help!! I get a lot of stress now.. If there is any solution, plz answer. - If reply doesn't work, contact me to branden04@naver.com