Cancelation of deceased fathers account

on the 25th of September I visited the Vaal mall store to cancel my fathers mtn contract as he had passed away and to port all of the numbers on his account to pre paid. The consultant made copies of his death certificate, his id and my id. she then stated that she is waiting for the system to updated when i asked her for a reference she said she could not provide me with one and that she would call me with an update almost 2 weeks later still have not received a call and when you phone the store there is no answer. Meanwhile his account is still running and charges are being added after i requested for it to be cancelled.