Very Risky Bank Zero Security

i have a debit order that went through to my account of R250 on 27 March 2024 and STD bank Eastrand cannot reverse it because this company put a block. While 2 weeks before the debit order went through went to the bank and asked the teller to stop the debit order and she told me that it is not guaranteed i should speak to the service provider, which i did. On 6 April 2024 i went to the bank again told the same teller that the debit order went through and can she please reverse the debit order and she told me that their is nothing she can do because the debit order is blocked. So i asked if they have a dispute department and she said no they don't have. This means that this company will debit my account forever and the bank cannot help me except if i change my account number and i must inform all the debit order companies to change the banking details.