Cell c not doing their part in cancelling contract now i hve to suffer

I had a contract with cell c wich i phoned in to cancel on 09/11/2021 cell c sent me an email confirming that they recieved my requests for cancellation nd that they would contact me with in two business days however the contracts was never cancelled and now i owe them over R7000 for contracts that i phoned in to cancel i have tried every way to get a hold of them but every time im told i dont pass the security check and wen i do get a hold of them they tell me they will conect me to retention department they just drop the phne in my ear this is giving me a bad record and i did my part to cancel