Vodacom Customer Service

I had a contract with Vodacom for 36 months which ended in July 2020, I contacted Vodacom walk in centre to iform them that i am not extending my contract with them, the walkin center advise e to call customer care which i did and the fone was never answered for days up until i decided to email Vodacom customer care to inform them that i am not renewing my contract. I never recieved feedback from Vodacom instead they kept on deducting the money which i reversed it. Now Vodacom is listing my name for not paying them and according to me i honored my contract till the end. I never used their data after 31 July they can verfy that aswell. The service i received from Vodacom was very bad, none of their customer care gave me a courtesy call as the contract was about to expire to check if i will carry on or not. From my side i send them an email a month before the contract expires to notify them about my intentions of not renewing and i resorted to email after not getting through their customer care lines and their branches are not counseling the contract. Kindly assist in clearing my name Thank you