Cancelation of Vodacom data line

Guys I posted before about a line I was trying to cancel and tried 3 times but still getting invoiced for the line every month. After posting Vodacom rep**** and said someone would contact me to help. I still have not received any phone call to to help me cancel this line. Also tried calling in again and was told I will get a reference number sms’t to me after logging and didn’t receive that either. The call center agent even said that she requested a credit on my account dating back. Well was still billed for that same line again this month. So I presume I will be paying on this line till the day I die or change my banking details.