Cancellation of deceased contract

My grandmother passed away on 01.08.2017. I notified Vodacom on 09.08.2017 via e-mail to cancel the contract which was to end on 10.09.2017. I received a reply and phone call to forward the necessary documents which was sent the next day as it had to be certified. I then enquired telephonically after not receiving any response again via e-mail and was sent from pillar to post and eventually told to go to a shop as I would not receive any information telephonically. I went to a Vodacom shop on 02.09.2017 and again the documentation was loaded and was told that I could enquire after 7 working days. I enquired again and was told that the request was loaded but not attended to. Left it again and enquired again after about 2 weeks and was told by the Vodacom shop to phone as they did not know what the message on the system meant. Phoned and was told to go to a shop. E-mailed and am still awaiting any response. The monthly airtime has been loaded since September and the account shows in arrears. Her bank account has been closed obviously. And the airtime has not even been used. I have a feeling that Vodacom is going to try and sue a dead person soon BUT surely the error is on their side? Vodacom is ANYONE even alive at your company? Will this ever be sorted out?