I’d use the usual feedback mechanisms provided by the Google Play Store (assuming that’s where you downloaded it from). The app isn’t really related to OSM and (at least where I am) doesn’t directly use OSM data.

Mine** says “2024”, so I suspect that the problem may be be at your end. Perhaps provide a few more details - what sort of phone, when and how you installed it, that sort of thing.

** I’m not in any way affiliated with Öffi other than as an occasional user - I use it as a more sane alternative to e.g. Google Maps which keeps trying to sell me crap I don’t want or offer connections that make no sense.