Direct axis not wanting to refund a incorrect payment

Hellopeter I hope that u can help. My mum as a loan with direct axis, that she is still paying even though we submitted all he information that she is retrenchment they still insisted on her paying. So we arrange to 50 per month as my mum is not working anymore which iam paying on her behalf. On the 22 of December 2023 I have them on my banking app as a benifisery so I pay my rent money in to there account by mistake and not the 50. I went to my bank to reverse but they said it was un successful. I called the server times the requested proof of payment and address my mum ID copy off which I sent. But yet still they have contacted us with any follow up. All they do is read my email and don't respond I need my money back, as I don't have a lone with I was just assisting my mum. I must say the service I got from Direct axis was very poor and unfair please assist me