Retention Department

On the 18th I called in to get my contracted settled and cancelled, The lady advised me to pay R324.87 then the contract will be settled. After i asked her 3 times i prefer a letter stating how much i must pay to settle she said unfortunately Cell C do not give letters for that. Today i called and they said THE SYSTEM saw it as a payment not a settlement, I need to pay another R170 odd rand to settle. I need someone to send me a letter ASAP. As i will not pay another cent towards Cell c if i dont get a settlement letter out of them