Did not agree for a wifi renewal

I cancelled the monthly wifi but I’m still being charged when I’ve said they should not renew the wifi contract I’m being charged for something I did not renew and not using at all I’ve called in countless times to ask for it to be cancelled but it was not cancelled and I did not agree for it to be renewed. How many times must I call vodacom to get them to stop de*****ing me and charging me for a service I’ve not been using . It’s pathetic what Vodacom is doing I feel exploited by vodacom