That's how it'll behave, if there is a tiny whisker short round the oscillator/crystal pins somewhere, or the crystal is not actually making contact. Oscillator can't start, so none of the time regist ...
I am trying to use MCP79522 with dspic33fj128GP710A controller without success. Able to read and write RTC and ram registers, but RTC not working. Reading the values same as written.