Refund declined

I contacted Telkom to change my bank details. I knew I was late in doing the change and understood there will be a return debit but on 29th January 2026 I did an EFT. Telkom decided they are going to debit me on 31st January after I made a manual payment. I was told to call back after 7 working days and request a refund. When I did call back the agent refused to even find out from management if he was not sure about a refund instead insisted in telling me I have a credit. I told him I want a refund and I will pay my account the end of February but he declined to help. Customer service stinks for this agent and he should learn to listen to his customer.