Upgrade of contracts without concent

A gentleman phoned me last week Thursday on my cellphone and explained that two of my Data contracts are open lines and if I want to change them to Top Up. He also said they will lower the premiums on my other contracts. The Gentlemen phoned me back later to request my Personal Details which i refused to give. Saturday I realised through SMS that all my contracts have been upgraded which I did not concent to. On Sunday i went to Vodacom in Kollenade to Cancell this. On Monday I phoned Ellite Mobile twice to cancell this and everytime they have a IT problem. No one has phoned me back up to now. Pathetic to say the least. They are phoning you everyday, 7 days a week to harass you but cant phone you back.