You most likely have something with the batteries, friend, since you are using the ps3 in 2022. My friends sometimes like to make this happen, but they don't care about the calendar and the time on PS3. Well, I would also advise you to watch guides or videos on YouTube, maybe some advice will help you. I don't know, if I were you, I would do a hard reset of the settings, and that's it. If it doesn't help, it's already a matter of components. And in general, why do you need this calendar in ps3 when there is an
Oriental Calendar, which is much more useful for your brain than a regular calendar that lags...