Allahabad Bank — transfer of my father sb account and stdr to my mother name

my father named as Ghanashyam das at-sapagadia, p.o-FCP has sb account and stdr at FerroChromeProject Allahabad bank branch of odisha.My father was dead on 25/05/2015 so kindly advise me how i transfer all acconuts of my father to my mother name at FerroChromeProject Branch.kindly gave advice through my gmail ([protected]@gmail.com)