Telkom blocks/stops routing to other networks, no technical support

I am trying to resolve a technical issue with my mobile router. I can send email from my phone to anyone using my ADSL link to Mweb, or my FNB Cell data, or any wifi hotspot for that matter, except my Telkom HUAIWEI router. The mail bounces back because it seems Telkom does not allow routing of my Mweb SMTP mail through their network. I have been trying for days to have this resolved without any luck. Calling and waiting hours for call centtres is a waste of time. They cannot comprehend the issue. I am stuck and likely to give the device back, even though everything else works fine using telkom data.