We have problem with udp ports 4950 & 4955 in Iran. ISP said (we don't restrict these ports). And also we have problem to access warframe's website. Port forwarding not working. Just VPN work that is not good.
To find out why this is occurring, I'd go to DEs forums and see if they might be able to explain.
But I call bad shenanigans (Western, possibly even Chinese sanctions may play a part. but I am not certain), yet I hope you can join us in WF soon.
It seems VPN might be the only workaround, but see if you can connect to a region closer to you that might not be the target of international sanctions.
What do you think?