Vision changes with age. If you have shortsightedness it can sometimes get better because your eyeballs can shrink with age, that means the image hitting the retina at the back of the eye comes back into better focus. On the other hand the lens in your eye can start to stiffen and the muscles around it don’t pull on it as well as when you are younger. So the lens does not focus as it used to. This is called presbyopia and tends to affect people over forty (if I remember). Hence vision can change with time. Worth getting an eye test?