Harassment and unprofessional call center for an account that doesn't exist

Account 3H1. ********** 4 - I have sent and resent all proof that this account has never been in arrears, had confirmation from Sophie Phiri that this would be dealt with. And then today another call centre agent phones me. As stated below – I want written confirmation that this matter is resolved, that there is no outstanding debt and that you will never phone me about this again. If I don’t receive this, I’m going to open a harassment case at the police, lodge a HelloPeter complaint and will do all in my power to get CarteBlanche to investigate this. I am sick and tired of your agents phoning me, when I say the account has been paid, they just drop the phone in my ear, a few weeks and one of them phone again.