Debit order deduction after confirmation of order was approved by company.

I have a fibre internet account with Vodacom since January 2020. I emailed them to cancelle my debit order as I had no money moving through that account. I paid them regularly every month before the 7th of each month cash at the Vodacom shop in ottery cape town . I received confirmation from Vodacom acknowledged that they have process my request and that the debit order has been cancelled. On Sunday 6 September 2020 my internet was off. I phoned in on *** number and was told that my service has been suspended because I have extra cost on my account and it was not paid up to date. And yet I am paying every months installment cash at the shop. They sent me a statement and on it is pennality fees charged to me because Vodacom could not debit my account for payment. They were still deducting via debit order after they sent me confirmation that it was cancelled months ago. This is the so called money that I owe them. The statement also shows a double deduction in May month. I have been phoning Vodacom since the 7th of this month with the same problem. I was told that a senior person namely Warren Henneker will phone me after I made the fist phone call on the 7th of the month. I was told that he will phone me as I cannot speak to him and my call cannot be forward to him. I will have to wait 24 to 48 hrs. It is almost 2 weeks coming this Sunday and I still heard nothing from him. I have a son who needs to use the internet for school. How long must I still wait for assistance?