Water damage few years ago, loads menu but software won’t load

Ok, so a while back my DSi got submerged in water about halfway and I didn’t do anything about it. I kept it for a few years and now it can apparently turn on, charge, load the menu, turn on camera, shuffle images on top screen, produce sound, but whenever I click on any application/software (like the settings or a game) it gives me an error. No error is specified so I’m not sure what to do. By the way, it can recognize games and the screen works perfectly fine. It’s just whenever I tap on any software the bottom screen gives me an error message.