Cellc is ignoring every attempt of mine to get a paid up letter for a cellphone contract that was cancelled 3 years ago, pathetic service provider

November 2021 my cellphone contract ended with Cellc, I received telephonic confirmation and an sms stating that my contract has been successfully cancelled, But March 2024 I go in a store to get a new cellphone contract and my application was denied because according to Transunion, Cellc has red flagged my account(which means it is in arrears), after 3 years Cellc has made no contact with me to state that my account has an outstanding balance of R70. I found out only when I went in to get a new contract. After weeks of trying to get someone to assist me, they gave me an email address for the collections queries department, I made payment into the banking details that Cellc gave to me and even sent through the proof of payment but to this day no response has been made to confirm that they received any of my mails. All I am asking for is for a paid up letter which was supposed to be given to me 3 years ago and for my account on Transunion to be update because at this moment I have a negative credit score. According to the call centre agents the collections queries department has no landlines number that you can contact so how is anybody supposed to received any help from them, I've been sending emails but got no response, Cellc is ignoring every attempt of mine to get what's due to me. I have been a customer of Cellc for almost 10 years but not anymore, I'm gonna change to vodacom, and I'd advise everyone else to change to vodacom, they have a customer service that actually helps their customers. Pathetic that I have to beg and plead for a paid up letter for a contract that was cancelled 3 years ago. Disgusting service from Cellc.