Poor services

I have a problem with telkom,I had a contract with them so the time that contract is coming to an end they phoned me for upgrading options ,so due to lockdowns 2020 had a financial problem due to pay cut so I told them to cancel my contract but they gave me option of giving me only benefit for R99 then I agreed so my benefits for previous contract was 500 mb data ,2 gb whatsapp data and 2 Sim cards telkom to telkom free calls.only to find out they gave me wrong benefits ,so at the end of August 2020 they said I owe them R1057 then I phoned them to dispute but they said I used extra data ,so I told them to cancel the contract they refused so I paid that R1057 and so I decided to brake the simcards and pay that R99 of contract till end of it .so only to find out at the end of September 2020 they came again and say I owe R2559 without using their Sim cards any more then I reversed that money so till now they give me problem the debit close to R7000 in my accounts every month