Remote connection only work from same wifi?

[Mr-Brightside]

So, my jellyfin server has always worked fine on the local network.

Now I want to setup remote access from the internet. I set it up, and it seemed to work, as entering the severs external IP address (double checked on whatsmyip.org) got me to my server. but when I tried actually accessing it from an external network it didn't work.

Could this be a DNS issue? Routing issue?