MTN SOUTH AFRICA -****S THAT ROB THE POOR AND DEFENSELESS

Can anyone please help me stop these vampires called MTN from robbing the widower of a deceased client of theirs. We supp**** all the necessary documents and requested the account to be closed. Three months later they are still deducting installments from a deceased persons bank account. After a great number of phone calls and emails they still do not respond by closing the account. PLEASE HELP!