The oldest son and now daughter also have equal rights can be karta in the said HUF based on the death certificate of father, the son can be appointed as karta of same, you can get in the PAN card of HUF the name change of the karta. Further in the bank accounts the name can be updated.
A request letter to change karta along with the death certificate and NOC from other coparceners can be filed with bank to change the karta.