Incorrect billing, although contract cancelled. Affecting Credit Score.

I ordered a pocket router in October 2024 but returned it within the same week due to dissatisfaction with Vodacom's services. I requested an immediate collection of the device, and Vodacom confirmed that it was collected by the appointed courier. Despite this, I continue to receive invoices for a device I have never used and no longer possess. I have contacted Vodacom’s call center multiple times, but the issue remains unresolved as they continually attempt to deduct monies via debit order. I started disputing the deduction and was forced to cancel the debit order with my bank and FNB reversed all debit orders. I made numerous phone calls to the service provider to which they have confirmed that the account is closed. Despite all my efforts and phone calls they still attempt to deduct monies from me and are now threatening legal action against me. Vodacom's standard has dropped and there is a lack of professionalism! Moving on to MTN. Clearly, the best service provider.