Mtn unauthorized contract

In 2020 Feb I lost my job due to covid I was then handed to debt collection and when I started to work again I settled the debt that I had with mtn but when I wasn't working they suspended my phone line and when I was finished paying the debt they reinstated my line but what they did was created a new contract with out my consent or authorization. They were supposed to reinstate the current contract and now I'm struggling to get hold of legal to rectify this mess because my current contract is coming to a end this month but the contract they created without my consent is ending in 2023 which I did not agree to so now I can't upgrade my phone. I'm tired of fighting with them I'm just going to cancel payments made to then or reverse the payment because I didn't give any consent for a new contract.