Unable to access my Mac desktop Manager program

Would anyone have experience with this error? I had an automatic MacBook OS update last night, and I might have had Manager open in the background, not sure. Is there a way to restore without losing 2 years of bookkeeping? The message begins as such, under the Businesses tab:

Access to the path ‘/Users/hillsideheather/Documents/Manager.io’ is denied.

System.UnauthorizedAccessException: Access to the path ‘/Users/hillsideheather/Documents/Manager.io’ is denied. —> System.IO.IOException: Operation not permitted — End of inner exception stack trace — at System.IO.Enumeration.FileSystemEnumerator`1.CreateDirectoryHandle(String path, Boolean ignoreNotFound) at System.IO.Enumeration.FileSystemEnumerator`1.Init() at System.IO.Enumeration.FileSystemEnumerable`1..ctor(String directory, FindTransform transform,