Pain and Suffering caused by Cell C's Debt Collector (SSDA)

I paid my Cell C account via SSDA, R 3322.16 paid on 29/01/2025 in full and final settlement per agreement with SSDA but that has not been updated and I have not received a paid up letter. I am now suffering the harassment of NuDebt for the same account and they have deducted R5000 from account without my consent. I need this resolved asap as I am preparing to open case of theft for the unauthorized debit and file a complaint with the Consumer Ombudsman for frustrations caused by your Debt Collectors.