Nedbank send imali service poor and offers no security

Accidentally sent a send-imali to the wrong number the other day. And when I called nedbank if they could reverse or stop the transaction I was told there was nothing that could be done unless the number doesn't exist and the transaction could be reversed in 7 days. 7 DAYS!! I understand that I made a mistake but there seems to be no security for such, ideally I should be getting an OTP and then the person would require that to draw the money but it seems to send the otp to the recipient anyways.