Good day Rob/
This would usually be based on the recipient's organisation security settings, they might be preventing your message from reaching the recipient from external IP. This means that the IP you're using to send mail is not authorised to send an email directly to Nedbank servers.
Please ensure that you are using the Afrihost SMTP relay .For more on Afrihost Internet Services settings, visit our Configuration Settings web page.
Another possible issue could be that your message was routed to the wrong email server.
Your domain's MX record might be the problem as well,so you will need to ensure that your domain has the correct MX records.
Should you need further assistance,
please feel free to send an email to email@example.com
or contact us on our WhatsApp helpline: https://whatsapp.afrihost.com
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or give us a call on our toll-free number 0800 011 000, available from 08h00 - 17h00 Monday - Friday.
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