Lost File

Hello!
Today I come to musescore to continue my project "Inspirational Movie Track". But....when I was going to open the sheet, I notice that there was an icon with a whithe cloud with a red background. I click in the sheet name top open, and the program have said that the sheet isnot from my acount and I can't open it. Anybody can help me solving this? And now I put the Factory Settings and the sheets name and icons all disapear.