Vodacom just taking money

I have cancelled my account via email with vodacom in august 2020. But yet they still kept taking their money off for my tablet which I never upgraded. Then I got a number to phone and phoned them again in February 2021 as nothing happened and said it was escalated to higher management. So I left it again waiting for someone to phone me. Then I decided to go into lakeside vodacom store the 15 May where I phoned from their store and spoke to Aleshan who gave me a reference of Aleshan. I then got told they will cancel it again. Then I got contacted 2 weeks ago to tell me my number is due for and upgrade. I politely told them that I am trying to cancel my number and do not want an upgrade as they phoned me 3 years after my upgrade date to ask me if I want one. Yet the end of May they still took off their money. So now I have paid vodacom for 10 months since my cancelation email. I would like someone higher up to contact me as I am really disappointed. Plus would like my money refunded.