No feedback from Vodacom for 5 Months

Hello Peter! I need your assistance please. On the 26 of March 2021 I called Vodacom to cancel one of my contracts. I followed up a week later to find out that they upgraded this specific contract. I specifically requested for it to be cancelled as this number is not in use and have not been for months. They said that they called me to upgrade the line and were looking into the recordings which will take 3-7 days, Its been 5 months and Vodacom is still billing me for this account. I need the contract cancelled as per my instruction on the 26 of March and refunded for the past 5 months immediately. I am utterly disappointed in Vodacom's service as I have been a loyal customer for may year. Not once have I upgraded only a sim card without taking a new phone. So I would not have agreed to upgrade the specific number.