So my father died and his all FDS got broken

I wanted to know he had fds of maybe upto 4. Than bank has said that he is now dead to all fd would be broken and all the money will be transferred to bank account. The fd had good interest and some of them were upto 2030 but the bank said no it will broken bcoz the person holder has died. It was govt bank. Is it real bcoz interst will also lose.so idk what to do.