********** cellphone upgrade

I have a contract with vodacom that was due to end in December 2020,and when I called vodacom to cancel the contract I was told that my lines were upgraded telephonically of which I never participated in.. Ive reported the matter to elite mobile ***** department but they don't call back just send emails and said the upgrades were canceled of which is not true... Ive sent numerous email and recently I've only received auto reply emails. If anyone has had the same problem please assist as month end is around the corner and I don't have money to pay and don't wanna be blacklisted.