Plex media servers appears offline

I have set up a plex media server, after struggling with permissions, my files finally show up in the plex web app. The server is listed on my phone and ipad, but it appears offline.

I'm new to Linux, but this is what I've tried: Restarting the service Logging in and out again Reinstalling plex

To be complete, my ipad and phone are on the same network as the server. And plex used to work when my pc still ran on Windows.

Edit: I'm on ubuntu 18.04.4. Ubuntu desktop

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