Non existent support at Telkom

I've been trying for months now to get Telkom to help me with my e-mail problem. I just get nothing out of them. Every time (that must be about more than 20 times now) I generate a fault report, they simply close it without phoning me to find out what my problem is. There is no way of contacting them except by phoning 10210. After speaking to them for about 5 minutes they just hang up the phone. Now they don't even bother to call me back as promised by their fault report acknowledgement. They don't even react to my fault reporting. Either they don't know how to fix it or they have nobody that knows anything about e-mail settings. My problem: Whenever I try and send e-mail from my Telkom account to people with vodamail, outlook.com, gmail or domain email addresses , it fails to be delivered and is returned to me with various reasons why it was blocked. Mainly because my e-mail is not secure enough or is considered as spam. If I send exactly the same messages from my gmail account, it is delivered without problems. I must mention that Telkom does not use authentication for their POP3 and SMTP servers and it seems that they don't even know what it is.