Rain is refusing to cancel my contract

I took a contract with Rain last year. I always had net work problems and I would spend money on data by purchasing from other cellular networks. I then decided to cancel it last year December when I went to the rain portal/app I couldn't find the cancel contract button, I the phones the number on the portal then I spoke to one of their agents He gave me a number to call for cancellation. When I phoned the number it rang unanswered I kept on holding until I eventually hung up. I tried to call the number again again it was unanswered. While I was busy struggling with the cancellation the bank card that I used when I was signing up for the contract expired. I tried again to contact rain but without success. Then I received a call from one of their agents telling me that my account is on erreas because I did not pay the amount in erreas was R579. I then told him that I want to cancel the contract as I have not been using it. He then gave me a number that is the same as the one I had been trying to reach I phoned but same story there was no answer. Then on the 4th of March I sent Rain a WhatsApp text telling them I want to cancel the contract as I no longer need it they gave me the same number that I have been failing to reach. Then towards the end of March I got a call from one their agents telling me that I owe them R1058 when I asked them what the money was for because I no longer use rain network they told me it's for keeping my account active the very same account I have been trying to cancel. I then phkned the number that they are not picking up and requested a call back. An agent phkned me the following day and she told me that she will not cancel the contract until I pay the R1058, she told me this amount will keep on accumulating until I pay the R1058 that I don't even know what is it for because I have to been using rain. Rain is a **** that wants to embezzlement funds from me. I will spend money on top of the one you are spending on the data contract. So this morning I received another call saying that I now owe R1587 because I have kept the account active. I have spoken to their agents about this they told me that the account will keep growing because I haven't canceled the account when I told them that I have spoken to their agents and they refused to cancel my contract with them they told me the account will not be canceled until I pay the R1587. I have stopped using rain in December now they want me to pay for not using the account.