Vodacom Cancelled contract - still being billed, unhelpful call center

I've cancelled my SIM only contract in October 2020 and I'm still being billed right till now, I am reversing all the debit orders however, you guys are still proceeding to bill me. I contacted your call center in November 2020 when I got billed and they told me that the contract has been cancelled and it was my last payment, my SIM card at the point was already broken and thrown away. Your call center can't even give me a reference number for my calls. I called again now yourll telling me that my contract was not cancelled??? I have email proof that it's been cancelled, I went to your store, I got that quote to cancel, there was no outstanding balance and I submitted the documents and got a reference number. What is the problem??? Why are you guys still debiting my account!!