My contract has expired, and Vodacom refuses to acknowledge the CPA

My contract has expired, and Vodacom refuses to acknowledge the CPA. They were supposed to contact me regarding the expiry of my iPad contract, and this was never done. On cancelling, I was told my last debit would be in June. This is utterly ridiculous, and more than 20 days notice, on a contract that has already lapsed, acknowledging there is no usage on the account, but refusal to have May 1st be the last debit date. I do not want the service, I just want it cancelled, but Vodacom has no right to take an extra month because of their refusal to follow the CPA. They cannot even prove that they have contacted me about the contract lapsing.