@Lakotaubp thanks for your help. I've just updated to 327 and tried everything you said but unforunately i can't get it to work yet. both of my sim cards are working on slot1 but not on slot2.
it could be a hardware issue as you said, i don't really want to flash android just to test it.
i checked the pins inside the phone and they look fine.
EDIT: I noticed it my device only shows the 1st slot IMEI when I dial *#06#
same on Settings > About, hope this can be helpful