It's not a game bug (because the code just literally can't do what you're describing) so it seems like something's happened to your phone in the interim.
Possibly you had a large OS update that messed up your data folder? Or you shuffled some files around (or an app did it) which has messed up some file hierarchies. Or your data folder has become read-only for some reason. Or you just need to fully power down your phone because some libraries or drivers decided to go a little mad. Or a dozen other issues (because technology is a Lovecraftian monster that obeys no rules or laws of man).
I'd try the power-down thing though; it solves about 90% of the weird issues reported here.
Sorry I can't be of more help!