Worst service provider

They are the worst service provider, I cursed I took their marketing call. I cancelled the contract and return the decoder in March 2025 and ever since they are debiting my account with R279.00 every month. I will call they will refund the money and come month end is another headache they debit once more. Now end of September and October they have debited again then I have to call for refund. The question is when this going to stop. What is more irritating their call centre agent every week they are calling selling their products even after making the request to stop calling me.