Vodacom-Finrite Worse service

I have a contract with Vodacom which ended in February but i renewed it with a downgrade , so i only renewed Data(1gig) and Airtime(R59) for R49 a month and i cancelled the phone insurance , as i no longer have the insured phone.. so each month i am suppose to be billed R49, but i am billed different amount from R179, R132, whenever i call Vodacom to ask why am i still billed for that Insurance even when i did the cancellation , i am told that they can see the cancellation and the issue has been escalated to IT to resolve so they can reimburse me all my money back dated from March, but to date nothing has been done, instead each month Vodacom keeps billing me, i am so fed-up infact i want them to cancel any service i have with them... they are so quick to bill us, but when they owe us their system fail to support the reversal of our money, it is my money and i am an unhappy customer