Archer C7 - OpenVPN not working

of course i've already followed the procedure as written here
https://www.tp-link.com/en/faq-1544.html

also, I've sent an email to tp-link customer service, but no answer yet

tp-link customer service replyed and helped me (suprisingly they were helpful and kind!)
i had my public ip under heavy nat - contacted my isp, they told me how to get a public ip, and now vpn works

epancini wrote

tp-link customer service replyed and helped me (suprisingly they were helpful and kind!)
i had my public ip under heavy nat - contacted my isp, they told me how to get a public ip, and now vpn works

I have an Archer AC 1200 v3 TP Link router and am using a Netgear LB 1120 LTE Modem with T-Mobile data plan. Can't get OpenVPN client to connect in, Can you share the advice they gave you on this thread so I can get mine working?

basically you need to contact T-Mobile and ask them if you can have a public ip.
my isp gives ip under nat by default. if you ask them, they'll give you a public ip for free with no guarantees (they can rollback the decision at any time). Or you can pay and rent a static ip.
I totally ignore T-Mobile policies so I can't say how they behave.

no I have not
I assume the router opens it automatically

(I don't a "Port Forwarding" page. There is "Virtual Servers" under the "NAT Forwarding" menu). Initially I've tried, cause I was suspecting that this was the issue, but I couldn't make it anyway since in the port page you can specify a network device in the router subnet, but not the router ip itselft)