@skogach 

Hi, thanks for posting question here~

The DDNS (Dynamic Domain Name System) feature allows users to remotely access their devices or local servers by assigning a domain name to their dynamic IP address.

You may log in to router's web management interface and go to Advanced > Network > Dynamic DNS > Select a DDNS service provider and configure it.

For more configuration details, please refer to: How to set up TP-LINK DDNS on TP-Link Wireless Router

Additionally, here are some tips for you if you are having trouble accessing the local server remotely via DDNS:

    1) Make sure the Port Forwarding settings are configured properly, make sure you are able to access the local server via the current public IP address of the Router.

    2) Use "nslookup your_ddns_name" or "dig your_ddns_name" on Windows/Mac OS to verify if the DDNS is working properly.

    3) For detailed troubleshooting, please refer to this FAQ: Troubleshooting Guide of DDNS function on TP-Link Wi-Fi Router, LTE Gateway Router or Deco Router

  @Marvin_S Hi, Sorry, I didn't mention that I'm trying to use TP-Link's DDNS provider and for this the router needs to be logged into the TP-Link ID service. But the problem is, it logs out every time I close router's web interface page.

  @Marvin_S Sorry, I checked It again and It actually logs out when I reboot the router, not when I just close the page. See here I logged In, there's my email.

After reboot there's TP-Link ID instead of email.