WHy do I get arrears notifications when I am NOT in arrears???

Cell C - I keep getting notifications from your Collections Department since October that my account is in arrears and that my service will be disconnected. I forwarded proof of payment for June, July, Aug, Sept, Oct and Nov. NOBODY acknowledged this (the email was sent to the collections dept and cell c customer service.) I AM NOT IN ARREARS. If SOMEBODY, ANYBODY, can just tell me what is going on we can sort this out. I tried your Customer service number just now and spoke to the most pathetic man in employment today. He wanted to smear me off on some automatic service and when I insisted to speak with flesh and blood he failed me on two security questions. My ID number and my bank. I pay per EFT from FNB which I told him and my ID number has certainly not changed. Please let me speak to somebody trained and competent and actually interested in delivering customer service