Terrible service From CELL C and Claiming i owe Money

I Had an account with CELL C in 2011 , i did go into default and was handed over in 2012 to a company called Pholosa Credit Group Which i payed off..... I called in Cell C Thursday 26th November 2020 to Try and take a contract and they have told me i still have a balance that's not written off , I was debt transferred to someone who could assist me and they logged a call and I received a reference number , i was told turn around time in 48hrs . i called back 1 December 2020 and i was told that my case is still open. i requested for the collect agencies number , which CELL C couldn't give me , which is utter ridiculous. after paying my account and After 8 years CELL C is saying i still owe them money. The service is terrible. I managed to get the contact details for the collection agency myself and it seems that they have shut down.... and its gone pass 72hrs and no feedbackj from CELL C