How do I fix it on android?
Android has internal and external storage. Internal Storage normaly only the app who is writing and reading the data has access. So you need to find a way to make the storage external for applications or you need to find a way to get access to the internal storage.
But also think about the problem, if you manage to change this storing behavior you old save files before in internal storage could still not accessable. Perhaps its possible to access the savefile in internal storage?