Vodacom contact cancellation not completed after sufficient notice was given

Vodacom has been providing utterly disgusting service. We have been trying to cancel a contract since April. We keep being told to call back the next month as the contract expired on 01 June. Now we are being told it can only cancel end July. This is a pensioner we are talking about, hence the contract needing to cancel as she cannot afford to pay R600+ per month. When asked for a manager as she needs this contract cancelled asap we are being told someone will call you back in Afrikaans! This is utterly pathetic. We have been calling since April to cancel for the end of contract and yet the contract has not been cancelled. Sort this out!! We can't keep calling and nothing is being done.