How can I get the root directory, of my shipped package?

//Save the path to “root” folder of the build game it works fine on editor but not in the package
PathToSave = FPaths::ConvertRelativePathToFull(FPaths::GameDir());

....

//here the second part of the code I use the preview variable and add folder/file it saves as 

// .bmp thats why I didnt use it

FScreenshotRequest testSR = FScreenshotRequest();
	testSR.RequestScreenshot(PathToSave + "ScreenShots/ScreenShot", false);

My problem is that, this code dosent work as a shipping package, it only works inside the editor or in the development package

Any tips Guys?? thanks a lot!

If it is still actual :

sDirectory = FPaths::ProjectSavedDir();
IFileManager& FileManager = IFileManager::Get();
sDirectory = FileManager.GetFilenameOnDisk(*sDirectory);